Slicers (applies to each fact value in each table cell)

Reporting Entity [Axis]

0000821189 (http://www.sec.gov/CIK)

Debt Disclosure [Abstract]	Period [Axis]
	2016-01-01 - 2016-12-31
Debt Disclosure [Abstract]
Long-Term Debt	Long-Term Debt at December 31, 2016 and 2015 consisted of the following (in thousands):   2016   2015         Commercial Paper $ —   $ 259,718 2.500% Senior Notes due 2016 —   400,000 5.875% Senior Notes due 2017 600,000   600,000 6.875% Senior Notes due 2018 350,000   350,000 5.625% Senior Notes due 2019 900,000   900,000 4.40% Senior Notes due 2020 500,000   500,000 2.45% Senior Notes due 2020 500,000   500,000 4.100% Senior Notes due 2021 750,000   750,000 2.625% Senior Notes due 2023 1,250,000   1,250,000 3.15% Senior Notes due 2025 500,000   500,000 4.15% Senior Notes due 2026 750,000   — 6.65% Senior Notes due 2028 140,000   140,000 3.90% Senior Notes due 2035 500,000   500,000 5.10% Senior Notes due 2036 250,000   — Long-Term Debt 6,990,000   6,649,718 Capital Lease Obligation 38,710   45,064 Less: Current Portion of Long-Term Debt 6,579   6,579 Unamortized Debt Discount 36,915   34,518 Debt Issuance Costs 5,437   4,774 Total Long-Term Debt $ 6,979,779   $ 6,648,911