Consolidated Statements of Changes In Shareholders' Equity (Parenthetical) (USD $)	6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012
Statement of Stockholders' Equity [Abstract]
Cash dividends (in dollars per share)	$ 0.6	$ 0.60
Class A Common Stock
Statement of Stockholders' Equity [Abstract]
Repurchase of common stock (in shares)	1,973	0
Class B Common Stock
Statement of Stockholders' Equity [Abstract]
Repurchase of common stock (in shares)	0	12,875