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	$ 16,382	$ 12,976	$ 8,110
Other comprehensive income, net:
Changes in defined benefit plan assets and benefit obligations, net	(24)	(559)	(139)
Unrealized gain (loss) on cash flow hedging instruments, net	1	(223)	(91)
Unrealized holding gains (losses) on securities, net of reclassification adjustment	1,355	4,095	(667)
Comprehensive income, net	$ 17,714	$ 16,289	$ 7,213