CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Parenthetical) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013		Mar. 31, 2012
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME [Abstract]
Unrealized holding losses on securities available-for-sale arising during period, tax effects	$ 1,507		$ 656
Reclassification adjustment for gains included in net income, tax effect	48		42
Unrealized gain on cash flow hedging derivatives, tax effect	(458)		(821)
Net actuarial gain arising during period, tax effect	(21)		(13)
Amortization of prior service cost included in net periodic cost, tax effect	$ (4)	[1]	$ (2)	[1]

[1] Reclassified into the consolidated statements of income in salaries and employee benefits.