Earnings Per Share (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Earnings Per Share [Abstract]
Net income	$ 15,244	$ 14,162
Weighted average shares outstanding - (in shares)	5,109,717	5,108,016
Net income per common share- basic and diluted (in dollars per share)	$ 2.98	$ 2.77