CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (USD $) In Thousands, except Share data, unless otherwise specified	Common Stock [Member]	Additional Paid-In Capital [Member]	Retained Earnings [Member]	Treasury Stock [Member]	Accumulated Other Comprehensive Loss [Member]	Total
Balance at Dec. 31, 2011	$ 3,143	$ 101,646	$ 42,960	$ (15,821)	$ (31,587)	$ 100,341
Balance (in shares) at Dec. 31, 2011	31,441,138
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income			62,303			62,303
Other comprehensive income/(loss)					(2,504)	(2,504)
Exercise of stock options	26	1,329				1,355
Exercise of stock options (in shares)	263,092
Vested restricted stock		(604)		604		0
Stock option expense		1,303				1,303
Restricted stock expense		446				446
Performance stock expense		53				53
Balance at Dec. 31, 2012	3,169	104,173	105,263	(15,217)	(34,091)	163,297
Balance (in shares) at Dec. 31, 2012	31,704,230
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income			25,915			25,915
Other comprehensive income/(loss)					15,129	15,129
Exercise of stock options	54	3,170				3,224
Exercise of stock options (in shares)	536,565
Vested restricted stock		(534)		534		0
Stock option expense		1,994				1,994
Restricted stock expense		427				427
Performance stock expense		404				404
Share based compensation tax windfall		131				131
Repurchase of shares				(301)		(301)
Balance at Dec. 31, 2013	3,223	109,765	131,178	(14,984)	(18,962)	210,220
Balance (in shares) at Dec. 31, 2013	32,240,795					32,240,795
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income			57,303			57,303
Other comprehensive income/(loss)					(26,019)	(26,019)
Exercise of stock options	61	4,142				4,203
Exercise of stock options (in shares)	596,135
Vested restricted stock		(161)		161		0
Stock option expense		2,491				2,491
Restricted stock expense		395				395
Performance stock expense		2,116				2,116
Share based compensation tax windfall		517				517
Balance at Dec. 31, 2014	$ 3,284	$ 119,265	$ 188,481	$ (14,823)	$ (44,981)	$ 251,226
Balance (in shares) at Dec. 31, 2014	32,836,930					32,836,930