Indemnity Capital Stock (Details 2) (Indemnity, Class A, USD $)	12 Months Ended	1 Months Ended					12 Months Ended
	Dec. 31, 2014	Jan. 31, 2014	May 31, 2014	Jun. 30, 2014	Jul. 31, 2013	Jan. 31, 2013	Dec. 31, 2013	Oct. 31, 2011
Shares repurchased outside of stock repurchase program
Total plan awards paid, share-based	$ 4,900,000
Performance shares
Shares repurchased outside of stock repurchase program
Shares repurchased outside of publicly announced stock repurchase program for share-based compensation awards (in shares)	64,398
Other Stock Based Awards
Shares repurchased outside of stock repurchase program
Total plan awards paid, share-based		201,411
Average price per share (in dollars per share)		$ 71.93
Other Stock Based Awards | Performance shares
Shares repurchased outside of stock repurchase program
Shares repurchased outside of publicly announced stock repurchase program for share-based compensation awards (in shares)		2,800
Stock compensation plan for outside directors
Shares repurchased outside of stock repurchase program
Total plan awards paid, share-based			552,503
Average price per share (in dollars per share)			$ 76.45
Stock compensation plan for outside directors | Performance shares
Shares repurchased outside of stock repurchase program
Shares repurchased outside of publicly announced stock repurchase program for share-based compensation awards (in shares)			7,227
Long-term incentive plan
Shares repurchased outside of stock repurchase program
Total plan awards paid, share-based				4,143,544	224,527	30,927	255,454
Average price per share (in dollars per share)				$ 76.21	$ 74.03	$ 69.65
Long-term incentive plan | Performance shares
Shares repurchased outside of stock repurchase program
Shares repurchased outside of publicly announced stock repurchase program for share-based compensation awards (in shares)				54,371	3,033	444	3,477
Stock repurchase program
Stock repurchases
Shares repurchased under stock repurchase program (in shares)	272,057						431,556
Total cost of shares repurchased under stock repurchase program	19,200,000						31,200,000
Amount of authorized stock repurchases approved for continuation under the current program								150,000,000
Approximate amount of repurchase authority remaining under the current stock repurchase program	$ 18,000,000