CONSOLIDATED CONDENSED STATEMENT OF SHAREHOLDERS' EQUITY (USD $) In Thousands, unless otherwise specified	Total	Common Stock	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Income	Treasury Stock
Beginning Balance at Dec. 31, 2013	$ 284,619	$ 783	$ 205,712	$ 77,038	$ 12,177	$ (11,091)
Beginning Balance (in shares) at Dec. 31, 2013		78,315				(967)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Acquisition of treasury stock (in shares)						(133)
Acquisition of treasury stock	(1,013)					(1,013)
Compensatory awards released from restriction (in shares)		58				8
Compensatory awards released from restriction		1	(87)			86
Exercise of stock options (in shares)						292
Exercise of stock options	2,222		(1,129)			3,351
Equity issuance costs	(7)		(7)
Share-based compensation	3,979		3,979
Stock dividends (in shares)		1
Stock dividends			9	(9)
Cash dividends	(2,330)			(2,330)
Equity adjustment from foreign currency translation	(4,808)				(4,808)
Net income	57,547			57,547
Ending Balance at Sep. 30, 2014	$ 340,209	$ 784	$ 208,477	$ 132,246	$ 7,369	$ (8,667)
Ending Balance (in shares) at Sep. 30, 2014		78,374				(800)