CONSOLIDATED STATEMENT OF SHAREHOLDERS' EQUITY (USD $) In Thousands, except Share data, unless otherwise specified	Total	Common Stock	Capital in Excess of Par Value	Retained Earnings	Treasury Stock
Balance at Dec. 31, 2012	$ 462,874	$ 923	$ 271,962	$ 210,003	$ (20,014)
Balance (in shares) at Dec. 31, 2012		92,374,539			5,424,847
Increase (Decrease) in Shareholders' Equity
Net income and comprehensive income	6,976			6,976
Stock-based compensation cost	3,028		3,028
Exercise of stock options	5,375	4	5,371
Exercise of stock options (in shares)		514,067
Vesting of restricted stock awards and units, net of shares withheld for employee tax	(1,483)	1	(1,484)
Vesting of restricted stock awards and units, net of shares withheld for employee tax (in shares)		95,920
Excess tax benefit from exercise of stock options	3,021		3,021
Balance at Mar. 31, 2013	$ 479,791	$ 928	$ 281,898	$ 216,979	$ (20,014)
Balance (in shares) at Mar. 31, 2013		92,984,526			5,424,847