Consolidated Statements of Comprehensive Income (Parenthetical) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Statement of Comprehensive Income [Abstract]
Net change in unrealized (losses) gains, tax expense (benefit)	$ (3,692)	$ 5,932	$ (893)	$ 11,537
Reclassification adjustment for gains, tax expense	181	139	352	358
Amortization of unrealized gain on securities reclassified to held-to-maturity, tax benefit	(120)	0	(120)	0
Change in unfunded pension liability related to unrealized (loss) gain, prior service cost and transition obligation, tax (benefit) expense	$ (9)	$ 36	$ (18)	$ 36