Subsequent Events (Details) (Subsequent Event [Member], USD $)	0 Months Ended	12 Months Ended
	Feb. 14, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Subsequent Event [Member]
Subsequent Event [Line Items]
Stock split conversion ratio	2
Earnings per common share:
Basic, pro forma		$ 4.56	$ 2.89	$ 1.95
Diluted, pro forma		$ 4.54	$ 2.88	$ 1.94