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	17,396			17,396
Stock-based compensation cost	6,122		6,122
Exercise of stock options	6,309	6	6,303
Exercise of stock options (in shares)		712,027
Vesting of restricted stock awards and units, net of shares withheld for employee tax	(1,498)	1	(1,499)
Vesting of restricted stock awards and units, net of shares withheld for employee tax (in shares)		99,265
Excess tax benefit from exercise of stock options	4,244		4,244
Balance at Jun. 30, 2013	$ 495,447	$ 930	$ 287,132	$ 227,399	$ (20,014)
Balance (in shares) at Jun. 30, 2013		93,185,831			5,424,847