Quoted Prices in Active Markets for Identical Assets | Significant Other Observable Inputs | Significant Unobservable Inputs | |||||||||||||||||||||||
(Level 1) | (Level 2) | (Level 3) | Total Assets | ||||||||||||||||||||||
(Dollars in Millions) | 2013 | 2012 | 2013 | 2012 | 2013 | 2012 | 2013 | 2012 | |||||||||||||||||
Short-term investment funds | $ | 304 | 155 | 561 | 627 | — | — | 865 | 782 | ||||||||||||||||
Government and agency securities | — | 53 | 1,965 | 1,706 | — | — | 1,965 | 1,759 | |||||||||||||||||
Debt instruments | — | 2 | 1,215 | 1,641 | 1 | 3 | 1,216 | 1,646 | |||||||||||||||||
Equity securities | 10,526 | 8,104 | 23 | 1 | 4 | 4 | 10,553 | 8,109 | |||||||||||||||||
Commingled funds | — | 11 | 5,846 | 4,985 | 44 | 50 | 5,890 | 5,046 | |||||||||||||||||
Insurance contracts | — | — | 2 | — | 23 | 24 | 25 | 24 | |||||||||||||||||
Other assets | 4 | — | 314 | 101 | 69 | 69 | 387 | 170 | |||||||||||||||||
Trust investments at fair value | $ | 10,834 | 8,325 | 9,926 | 9,061 | 141 | 150 | 20,901 | 17,536 | ||||||||||||||||