Consolidated Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014		Mar. 31, 2013
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 8,136		$ 7,189
Unrealized gains (losses) on securities:
Unrealized holding gain (loss) on securities arising during the period	9,121	[1]	(1,093)	[1]
Income tax effect	(3,193)	[1]	383	[1]
Less: reclassification adjustment for gains on securities included in net income	(2,832)		0
Income tax effect	992		0
Net unrealized gains/ (losses)	4,088		(710)
Unrealized gains on cash flow hedges:
Unrealized gain on cash flow hedges arising during the period	664		0
Income tax effect	(232)		0
Net unrealized gains	432		0
Other comprehensive income (loss), net of tax	4,520		(710)
Comprehensive income	$ 12,656		$ 6,479

[1] Includes immaterial gains on foreign currency items for the first quarter 2014.