Consolidated Statement of Stockholders' Equity - USD ($) shares in Thousands	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	AOCI Attributable to Parent [Member]	Treasury Stock [Member]	Deferred Compensation Expense [Member]	Total
Balance at Dec. 31, 2012	$ 266,000	$ 389,881,000	$ 579,062,000	$ 59,875,000	$ (11,533,000)	$ 10,331,000	$ 1,027,882,000
Balance (in shares) at Dec. 31, 2012					(367)
Net income (loss)			$ 70,606,000				70,606,000
Issuance of common stock	$ 3,000	$ 10,258,000					10,261,000
Exercise of stock options		282,000					282,000
Tax benefit on options exercised		1,608,000					1,608,000
Deferred compensation plan		$ 257,000			$ 4,041,000	$ (4,041,000)	257,000
Deferred compensation plan (in shares)					133
Stock repurchases					$ (11,198,000)		(11,198,000)
Stock repurchases (in shares)					(315)
Cash dividends declared			$ (26,447,000)				(26,447,000)
Translation adjustment				$ (9,910,000)			(9,910,000)
Balance at Dec. 31, 2013	$ 269,000	$ 402,286,000	$ 623,221,000	$ 49,965,000	$ (18,690,000)	$ 6,290,000	1,063,341,000
Balance (in shares) at Dec. 31, 2013					2,515
Deferred compensation plan (in shares)					(133)
Stock repurchases					$ 11,198,000		11,198,000
Foreign currency and other loss				$ (9,910,000)			(9,910,000)
Net income (loss)			$ 62,375,000				62,375,000
Issuance of common stock	$ 2,000	$ 8,190,000					8,192,000
Deferred compensation plan		$ 165,000			$ (1,254,000)	$ 1,254,000	165,000
Deferred compensation plan (in shares)					37
Stock repurchases					$ 58,497,000		58,497,000
Stock repurchases (in shares)					(1,898)
Cash dividends declared			$ (26,193,000)				(26,193,000)
Translation adjustment				$ (80,630,000)			(80,630,000)
Balance at Dec. 31, 2014	$ 271,000	$ 410,641,000	$ 659,403,000	$ (30,665,000)	$ (78,441,000)	$ 7,544,000	968,753,000
Balance (in shares) at Dec. 31, 2014					(2,484)
Deferred compensation plan (in shares)					(37)
Stock repurchases					$ (58,497,000)		(58,497,000)
Foreign currency and other loss				$ (80,630,000)			(80,630,000)
Net income (loss)			$ (215,235,000)				(215,235,000)
Issuance of common stock	$ 3,000	$ 9,890,000					9,893,000
Deferred compensation plan		$ (3,242,000)			$ (1,176,000)	$ 1,176,000	(3,242,000)
Deferred compensation plan (in shares)					104
Translation adjustment				$ (65,569,000)			(65,569,000)
Balance at Dec. 31, 2015	$ 274,000	$ 417,289,000	$ 444,181,000	(96,234,000)	$ (75,922,000)	$ 8,720,000	698,308,000
Balance (in shares) at Dec. 31, 2015					(2,543)
Deferred compensation plan (in shares)					(104)
Foreign currency and other loss				$ (65,569,000)			(65,569,000)
Treasury stock activity (net)					$ 3,695,000		3,695,000
Treasury stock activity (net) (in shares)					45
Forfeiture of dividends			$ 13,000				$ 13,000