Consolidated Statement of Stockholders' Equity (USD $) In Thousands	Total	Common Stock	Additional Paid-in-Capital	Retained Earnings	Accumulated Other Comprehensive Income (Loss)	Treasury Stock
Beginning balance at Dec. 31, 2014	$ 978,010	$ 257	$ 286,854	$ 852,057	$ (81,984)	$ (79,174)
Beginning balance, shares at Dec. 31, 2014		25,724
Net income	35,815	0	0	35,815	0	0
Other comprehensive income (loss), net of tax	(35,140)	0	0	0	(35,140)	0
Treasury Stock, Value, Acquired, Cost Method	(17,717)					(17,717)
Issuance of Common and Treasury Shares to Employee Benefit Plans Shares		28
Issuance of common and treasury shares to employee benefit plans	(2,141)	1	(8,791)	0	0	6,649
Stock-based compensation	4,873	0	4,873	0	0	0
Tax effect from options exercised and the vesting of restricted shares	1,004	0	1,004	0	0	0
Cash dividends	(4,877)	0	0	(4,877)	0	0
Ending balance at Mar. 31, 2015	$ 959,827	$ 258	$ 283,940	$ 882,995	$ (117,124)	$ (90,242)
Ending balance, shares at Mar. 31, 2015		25,752