| Defined Benefit Pension Plans and Defined Benefit Postretirement Plans Disclosure [Abstract] | Period [Axis] |
|---|
2016-01-01 - 2016-12-31 |
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Defined Benefit Pension Plans and Defined Benefit Postretirement Plans Disclosure [Abstract] | |
Reconciliation Of The Benefit Obligation | The reconciliation of the benefit obligation is as follows: | | | | | | | | | | | | | | | | | | Pension Benefits | | Other Benefits | | 2016 | | 2015 | | 2016 | | 2015 | Benefit obligation at beginning of year | $ | 1,833.3 |
| | $ | 1,914.4 |
| | $ | 578.7 |
| | $ | 646.6 |
| Service cost | 11.6 |
| | 13.1 |
| | 1.6 |
| | 2.1 |
| Interest cost | 68.5 |
| | 68.2 |
| | 22.4 |
| | 23.4 |
| Plan amendment | — |
| | 0.8 |
| | — |
| | — |
| Actuarial loss (gain) | 32.2 |
| | (41.2 | ) | | (4.2 | ) | | (58.1 | ) | Benefits paid | (120.7 | ) | | (122.0 | ) | | (33.3 | ) | | (35.3 | ) | Benefit obligation at end of year | $ | 1,824.9 |
| | $ | 1,833.3 |
| | $ | 565.2 |
| | $ | 578.7 |
|
|
Changes In The Fair Value Of Plan Assets | The changes in the fair value of plan assets are as follows: | | | | | | | | | | | | | | | | | | Pension Benefits | | Other Benefits | | 2016 | | 2015 | | 2016 | | 2015 | Fair value of plan assets at beginning of year | $ | 1,865.2 |
| | $ | 1,985.0 |
| | $ | 328.4 |
| | $ | 347.9 |
| Actual return on plan assets | 132.2 |
| | (1.5 | ) | | 21.8 |
| | (1.2 | ) | Employer contributions | 11.1 |
| | 3.7 |
| | 14.9 |
| | 17.3 |
| Benefits paid | (120.7 | ) | | (122.0 | ) | | (33.3 | ) | | (35.6 | ) | Fair value of plan assets at end of year | $ | 1,887.8 |
| | $ | 1,865.2 |
| | $ | 331.8 |
| | $ | 328.4 |
|
|
Net Amount Included In Consolidated Balance Sheets | The net amount included in the consolidated balance sheets is as follows: | | | | | | | | | | | | | | | | | | Pension Benefits | | Other Benefits | | 2016 | | 2015 | | 2016 | | 2015 | Noncurrent assets | $ | 126.7 |
| | $ | 103.4 |
| | $ | — |
| | $ | — |
| Current liabilities | (3.7 | ) | | (10.5 | ) | | — |
| | — |
| Noncurrent liabilities | (60.1 | ) | | (61.0 | ) | | (233.4 | ) | | (250.3 | ) | Net amount at December 31 | $ | 62.9 |
| | $ | 31.9 |
| | $ | (233.4 | ) | | $ | (250.3 | ) |
|
Net Amounts Included In Accumulated Other Comprehensive Loss (Income) That Have Not Been Recognized As Components Of Net Periodic Benefit Costs | The net amounts included in accumulated other comprehensive loss that have not been recognized as components of net periodic benefit costs are as follows: | | | | | | | | | | | | | | | | | | Pension Benefits | | Other Benefits | | 2016 | | 2015 | | 2016 | | 2015 | Net actuarial loss | $ | 655.8 |
| | $ | 635.0 |
| | $ | 146.6 |
| | $ | 162.7 |
| Prior service cost (credit) | 0.5 |
| | (0.1 | ) | | (59.7 | ) | | (73.5 | ) | Net amount before tax at December 31 | $ | 656.3 |
| | $ | 634.9 |
| | $ | 86.9 |
| | $ | 89.2 |
|
|
Schedule Of Assumptions Used In Calculating The Benefit Obligations | The weighted-average assumptions used in calculating the benefit obligations for all plans are as follows: | | | | | | | | | | | | | | Pension Benefits | | Other Benefits | | 2016 | | 2015 | | 2016 | | 2015 | Discount rate | 3.77 | % | | 3.92 | % | | 3.82 | % | | 4.01 | % | Rate of compensation increase | 3.00 | % | | 3.00 | % | | 3.00 | % | | 3.00 | % | Expected rate of return on plan assets | 7.95 | % | | 7.84 | % | | 7.00 | % | | 7.00 | % |
|
Components Of Net Periodic Benefit Cost (Credit) | The components of net periodic benefit cost (benefit credit) included in the consolidated statements of income are as follows: | | | | | | | | | | | | | | 2016 | | 2015 | | 2014 | Pension Benefits | | | | | | Service cost | $ | 11.6 |
| | $ | 13.1 |
| | $ | 13.0 |
| Interest cost | 68.5 |
| | 68.2 |
| | 74.1 |
| Expected return on assets | (147.1 | ) | | (143.2 | ) | | (137.5 | ) | Recognized actuarial loss | 19.0 |
| | 25.7 |
| | 21.0 |
| Amortization of prior service credit | (0.6 | ) | | (0.6 | ) | | (0.8 | ) | Settlement loss | 7.3 |
| | 6.5 |
| | 5.2 |
| Net periodic benefit credit | $ | (41.3 | ) | | $ | (30.3 | ) | | $ | (25.0 | ) | | | | | | | Other Benefits | | | | | | Service cost | $ | 1.6 |
| | $ | 2.1 |
| | $ | 3.2 |
| Interest cost | 22.4 |
| | 23.4 |
| | 26.3 |
| Expected return on assets | (22.4 | ) | | (23.7 | ) | | (23.4 | ) | Recognized actuarial loss | 12.4 |
| | 15.3 |
| | 9.4 |
| Amortization of prior service credit | (13.8 | ) | | (14.4 | ) | | (14.4 | ) | Net periodic benefit cost | $ | 0.2 |
| | $ | 2.7 |
| | $ | 1.1 |
|
|
Weighted-Average Assumptions Used In Calculating The Benefit Obligations For All Plans | The weighted-average assumptions used in calculating the net periodic benefit cost for all plans are as follows: | | | | | | | | | | | 2016 | | 2015 | | 2014 | Pension Benefits | | | | | | Discount rate | 3.92 | % | | 3.66 | % | | 4.39 | % | Rate of compensation increase | 3.00 | % | | 3.00 | % | | 3.00 | % | Expected rate of return on plan assets | 7.84 | % | | 7.62 | % | | 7.66 | % | | | | | | | Other Benefits | | | | | | Discount rate | 4.01 | % | | 3.74 | % | | 4.48 | % | Rate of compensation increase | 3.00 | % | | 3.00 | % | | 3.00 | % | Expected rate of return on plan assets | 7.00 | % | | 7.00 | % | | 7.00 | % |
|
Fair Values of Pension Benefit Assets and Other Benefit Assets by Asset Category and Level Inputs | The fair values of our pension benefit assets and other benefit assets by asset category and level inputs at December 31, 2016, excluding cash, investment income receivable and amounts due to/from brokers, resulting in a net asset of $2.8, are as follows (see Note 6, “Fair Value,” for additional information regarding the definition of level inputs): | | | | | | | | | | | | | | | | | | Level I | | Level II | | Level III | | Total | December 31, 2016 | | | | | | | | Pension Benefit Assets: | | | | | | | | Equity securities: | | | | | | | | U.S. securities | $ | 561.4 |
| | $ | 4.4 |
| | $ | — |
| | $ | 565.8 |
| Foreign securities | 264.5 |
| | — |
| | — |
| | 264.5 |
| Mutual funds | 36.6 |
| | — |
| | — |
| | 36.6 |
| Fixed maturity securities: | | | | | | | | Government securities | 183.9 |
| | — |
| | — |
| | 183.9 |
| Corporate securities | — |
| | 385.9 |
| | — |
| | 385.9 |
| Asset-backed securities | — |
| | 134.7 |
| | — |
| | 134.7 |
| Other types of investments: | | | | | | | | Common and collective trusts | — |
| | 27.5 |
| | — |
| | 27.5 |
| Partnership interests | — |
| | — |
| | 112.5 |
| | 112.5 |
| Insurance company contracts | — |
| | — |
| | 173.3 |
| | 173.3 |
| Treasury futures contracts | 0.3 |
| | — |
| | — |
| | 0.3 |
| Total pension benefit assets | $ | 1,046.7 |
| | $ | 552.5 |
| | $ | 285.8 |
| | $ | 1,885.0 |
| | | | | | | | | Other Benefit Assets: | | | | | | | | Equity securities: | | | | | | | | U.S. securities | $ | 13.0 |
| | $ | 0.2 |
| | $ | — |
| | $ | 13.2 |
| Foreign securities | 5.4 |
| | — |
| | — |
| | 5.4 |
| Mutual funds | 47.1 |
| | — |
| | — |
| | 47.1 |
| Fixed maturity securities: | | | | | | | | Government securities | 2.7 |
| | — |
| | — |
| | 2.7 |
| Corporate securities | — |
| | 7.9 |
| | — |
| | 7.9 |
| Asset-backed securities | — |
| | 5.8 |
| | — |
| | 5.8 |
| Other types of investments: | | | | | | | | Common and collective trusts | — |
| | 1.0 |
| | — |
| | 1.0 |
| Partnership interests | — |
| | — |
| | 1.2 |
| | 1.2 |
| Life insurance contracts | — |
| | — |
| | 237.7 |
| | 237.7 |
| Investment in DOL 103-12 trust | — |
| | 9.8 |
| | — |
| | 9.8 |
| Total other benefit assets | $ | 68.2 |
| | $ | 24.7 |
| | $ | 238.9 |
| | $ | 331.8 |
|
The fair values of our pension benefit assets and other benefit assets by asset category and level inputs at December 31, 2015, excluding cash, investment income receivable and amounts due to/from brokers, resulting in a net asset of $3.4, are as follows (see Note 6, “Fair Value,” for additional information regarding the definition of level inputs): | | | | | | | | | | | | | | | | | | Level I | | Level II | | Level III | | Total | December 31, 2015 | | | | | | | | Pension Benefit Assets: | | | | | | | | Equity securities: | | | | | | | | U.S. securities | $ | 542.8 |
| | $ | 4.4 |
| | $ | — |
| | $ | 547.2 |
| Foreign securities | 258.8 |
| | — |
| | — |
| | 258.8 |
| Mutual funds | 34.7 |
| | — |
| | — |
| | 34.7 |
| Fixed maturity securities: | | | | | | | | Government securities | 176.6 |
| | — |
| | — |
| | 176.6 |
| Corporate securities | — |
| | 364.0 |
| | — |
| | 364.0 |
| Asset-backed securities | — |
| | 141.1 |
| | — |
| | 141.1 |
| Other types of investments: | | | | | | | | Common and collective trusts | — |
| | 48.1 |
| | — |
| | 48.1 |
| Partnership interests | — |
| | — |
| | 117.1 |
| | 117.1 |
| Insurance company contracts | — |
| | — |
| | 174.2 |
| | 174.2 |
| Total pension benefit assets | $ | 1,012.9 |
| | $ | 557.6 |
| | $ | 291.3 |
| | $ | 1,861.8 |
| | | | | | | | | Other Benefit Assets: | | | | | | | | Equity securities: | | | | | | | | U.S. securities | $ | 16.8 |
| | $ | 0.3 |
| | $ | — |
| | $ | 17.1 |
| Foreign securities | 7.4 |
| | — |
| | — |
| | 7.4 |
| Mutual funds | 36.6 |
| | — |
| | — |
| | 36.6 |
| Fixed maturity securities: | | | | | | | | Government securities | 3.8 |
| | — |
| | — |
| | 3.8 |
| Corporate securities | — |
| | 9.5 |
| | — |
| | 9.5 |
| Asset-backed securities | — |
| | 7.7 |
| | — |
| | 7.7 |
| Other types of investments: | | | | | | | | Common and collective trusts | — |
| | 1.5 |
| | — |
| | 1.5 |
| Partnership interests | — |
| | — |
| | 1.5 |
| | 1.5 |
| Life insurance contracts | — |
| | — |
| | 229.9 |
| | 229.9 |
| Investment in DOL 103-12 trust | — |
| | 13.4 |
| | — |
| | 13.4 |
| Total other benefit assets | $ | 64.6 |
| | $ | 32.4 |
| | $ | 231.4 |
| | $ | 328.4 |
|
|
Reconciliation Of The Beginning And Ending Balances Of Plan Assets Measured At Fair Value Using Level III Inputs | A reconciliation of the beginning and ending balances of plan assets measured at fair value using Level III inputs for the years ended December 31, 2016, 2015 and 2014 is as follows: | | | | | | | | | | | | | | | | | | Partnership Interests | | Insurance Company Contracts | | Life Insurance Contracts | | Total | Year ended December 31, 2016 | | | | | | | | Beginning balance at January 1, 2016 | $ | 118.6 |
| | $ | 174.2 |
| | $ | 229.9 |
| | $ | 522.7 |
| Actual return on plan assets: | | | | | | | | Relating to assets still held at the reporting date | (3.5 | ) | | (3.1 | ) | | 10.8 |
| | 4.2 |
| Purchases | 17.8 |
| | 8.9 |
| | — |
| | 26.7 |
| Sales | (19.2 | ) | | (6.7 | ) | | (3.0 | ) | | (28.9 | ) | Ending balance at December 31, 2016 | $ | 113.7 |
| | $ | 173.3 |
| | $ | 237.7 |
| | $ | 524.7 |
| | | | | | | | | Year ended December 31, 2015 | | | | | | | | Beginning balance at January 1, 2015 | $ | 122.2 |
| | $ | 187.7 |
| | $ | 238.4 |
| | $ | 548.3 |
| Actual return on plan assets: | | | | | | | | Relating to assets still held at the reporting date | (5.9 | ) | | (5.7 | ) | | (6.8 | ) | | (18.4 | ) | Purchases | 10.9 |
| | 7.0 |
| | — |
| | 17.9 |
| Sales | (8.6 | ) | | (14.8 | ) | | (1.7 | ) | | (25.1 | ) | Ending balance at December 31, 2015 | $ | 118.6 |
| | $ | 174.2 |
| | $ | 229.9 |
| | $ | 522.7 |
| | | | | | | | | Year ended December 31, 2014 | | | | | | | | Beginning balance at January 1, 2014 | $ | 160.3 |
| | $ | 197.4 |
| | $ | 230.0 |
| | $ | 587.7 |
| Actual return on plan assets: | | | | | | | | Relating to assets still held at the reporting date | (5.4 | ) | | 1.4 |
| | 8.4 |
| | 4.4 |
| Purchases | 8.4 |
| | 11.6 |
| | — |
| | 20.0 |
| Sales | (41.1 | ) | | (22.7 | ) | | — |
| | (63.8 | ) | Ending balance at December 31, 2014 | $ | 122.2 |
| | $ | 187.7 |
| | $ | 238.4 |
| | $ | 548.3 |
|
|
Estimated Future Payments For Pension Benefits And Postretirement Benefits | Our estimated future payments for pension benefits and postretirement benefits, which reflect expected future service, as appropriate, are as follows: | | | | | | | | | | Pension Benefits | | Other Benefits | 2017 | $ | 157.9 |
| | $ | 41.4 |
| 2018 | 154.0 |
| | 42.2 |
| 2019 | 153.1 |
| | 42.5 |
| 2020 | 147.8 |
| | 42.5 |
| 2021 | 143.0 |
| | 42.2 |
| 2022 – 2026 | 637.6 |
| | 197.4 |
|
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