CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME [Abstract]
Net income	$ 20,393	$ 19,457	$ 18,392
Other comprehensive income (loss):
Net unrealized gains (losses) on available-for-sale securities	(1,011)	34,851	(7,768)
Change in funded status of pension plan	(561)	(3,172)	(633)
Other comprehensive income (loss) before income taxes	(1,572)	31,679	(8,401)
Income tax expense (benefit)	(624)	12,575	(3,334)
Other comprehensive income (loss)	(948)	19,104	(5,067)
Comprehensive Income	$ 19,445	$ 38,561	$ 13,325