CONSOLIDATED STATEMENTS OF FINANCIAL POSITION (Parenthetical) (USD $) In Millions, except Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Fixed maturities, amortized cost	$ 9,095
Cash and cash equivalents	514	452
Other assets	501	451
Indemnity
Fixed maturities, amortized cost	555	518
Equity securities, cost	24	50
Limited partnerships, cost	89	123
Cash and cash equivalents	92	49
Other assets	127	114
Treasury stock (in shares)	22,110,132	21,838,075
Exchange
Fixed maturities, amortized cost	8,540	7,801
Equity securities, cost	788	778
Trading securities, cost	2,289	2,198
Limited partnerships, cost	694	790
Cash and cash equivalents	422	403
Other assets	$ 374	$ 337
Class A | Indemnity
Common stock, stated value per share (in dollars per share)	$ 0.0292	$ 0.0292
Common stock, authorized (in shares)	74,996,930	74,996,930
Common stock, issued (in shares)	68,299,200	68,299,200
Common stock, outstanding (in shares)	46,189,068	46,461,125
Class B | Indemnity
Ratio for converting shares of Class B common stock into shares of Class A common stock (as a percent)	2400.00%	2400.00%
Common stock, stated value per share (in dollars per share)	$ 70	$ 70
Common stock, authorized (in shares)	3,070	3,070
Common stock, issued (in shares)	2,542	2,542
Common stock, outstanding (in shares)	2,542	2,542