Indemnity Earnings Per Share (Details) (Indemnity, USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Dec. 31, 2013
Class A
Income available to stockholders (Basic EPS:)
Allocated net income (numerator) (in dollars)	$ 49	$ 44	$ 94	$ 80
Weighted shares (denominator) (in shares)	46,214,153	46,693,333	46,307,659	46,733,925
Per-share amount (in dollars per share)	$ 1.05	$ 0.95	$ 2.04	$ 1.73
Dilutive effect of stock-based awards
Allocated net income (numerator) (in dollars)	0	0	0	0
Weighted shares (denominator) (in shares)	96,461	92,126	96,461	92,126
Assumed conversion of Class B shares
Allocated net income (numerator) (in dollars)	0	0	1	1
Weighted shares (denominator) (in shares)	6,100,800	6,100,800	6,100,800	6,100,800
Income available to stockholders on equivalent shares (Diluted EPS:)
Allocated net income (numerator) (in dollars)	49	44	95	81
Weighted shares (denominator) (in shares)	52,411,414	52,886,259	52,504,920	52,926,851
Per-share amount (in dollars per share)	$ 0.94	$ 0.84	$ 1.82	$ 1.54
Class B
Reconciliation of the numerators and denominators used in the basic and diluted per-share computations
Ratio for converting shares of Class B common stock into shares of Class A common stock (as a percent)	2400.00%		2400.00%		2400.00%
Income available to stockholders (Basic EPS:)
Allocated net income (numerator) (in dollars)	0	0	1	1
Weighted shares (denominator) (in shares)	2,542	2,542	2,542	2,542
Per-share amount (in dollars per share)	$ 158.00	$ 142.00	$ 307.00	$ 259.00
Income available to stockholders on equivalent shares (Diluted EPS:)
Allocated net income (numerator) (in dollars)	$ 0	$ 0	$ 1	$ 1
Weighted shares (denominator) (in shares)	2,542	2,542	2,542	2,542
Per-share amount (in dollars per share)	$ 158.00	$ 142.00	$ 307.00	$ 259.00