UNAUDITED CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (USD $) In Thousands, unless otherwise specified	Total	Common Stock	Shares Held Under Employee Participation Plan	Additional Paid-in Capital	Accumulated Other Comprehensive Loss	Accumulated Earnings
Balance at Dec. 31, 2013	$ 1,475,639	$ 607	$ (469)	$ 898,165	$ (19,556)	$ 596,892
Balance (in shares) at Dec. 31, 2013		60,672
Increase (Decrease) in Stockholders' Equity
Net income	8,960					8,960
Other comprehensive loss	(41,525)				(41,525)
Stock-based compensation	2,278			2,278
Stock-based compensation (in shares)		42
Issuance of restricted shares, net of shares remitted	(750)			(750)
Issuance of restricted shares, net of shares remitted (in shares)		(14)
Repurchases of common stock	(1,225)			(1,225)
Repurchases of common stock (in shares)		(25)
Net tax benefit on exercise of stock-based awards	117			117
Net tax benefit on exercise of stock-based awards (in shares)		0
Employee stock purchase plan	2,141			2,141
Employee stock purchase plan (in shares)		43
Balance at Mar. 31, 2014	$ 1,445,635	$ 607	$ (469)	$ 900,726	$ (61,081)	$ 605,852
Balance (in shares) at Mar. 31, 2014		60,718