CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Statement of Comprehensive Income [Abstract]
Net income	$ 573	$ 1,048	$ 619
Other comprehensive (loss) income
Change in unrealized holding gains (losses) on available-for-sale securities, net of tax (expense) benefit of $(42), $125, and $(121), respectively	78	(232)	224
Reclassification adjustment for gross (gains) losses included in net income, net of tax benefit (expense) of $10, $(3) and $23, respectively	(18)	7	(44)
Postretirement plans, net of tax (benefit) expense of $(31), $44 and $(17), respectively	(60)	81	(30)
Other comprehensive (loss) income	0	(144)	150
Comprehensive income	573	904	769
Less: Comprehensive income attributable to noncontrolling interest in consolidated entity – Exchange	464	667	637
Total comprehensive income – Indemnity	$ 109	$ 237	$ 132