Consolidated Statement of Stockholders' Equity - USD ($) $ in Thousands	Stockholders' Equity of the Company Common Stock [Member]	Stockholders' Equity of the Company Treasury Stock [Member]	Stockholders' Equity of the Company Additional Paid-in Capital [Member]	Accumulated Other Comprehensive Income (Loss)	Stockholders' Equity of the Company Retained Earnings [Member]	Noncontrolling Interest [Member]	Total
Beginning balance, value at Dec. 31, 2016				$ (126,964)
Net income							$ 35,961
Dividends distributed to noncontrolling interest							(1,800)
Foreign currency translation adjustments							$ 9,567
Ending balance, value at Jun. 30, 2017				(104,707)
Preferred stock beginning balance, share at Dec. 31, 2017							0
Common stock beginning balance, share at Dec. 31, 2017	45,862,000						45,861,959
Beginning balance, value at Dec. 31, 2017	$ 459	$ (615,677)	$ 351,725	(102,304)	$ 721,664	$ 6,978	$ 362,845
Net income					10,109	2,120	12,229
Dividends to shareholders					(12,414)		(12,414)
Dividends distributed to noncontrolling interest						(1,125)	(1,125)
Foreign currency translation adjustments				(25,722)		(162)	(25,884)
Derivatives valuation, net of tax				(1,513)			(1,513)
Vesting of restricted stock units, share	172,000
Vesting of restricted stock units, value	$ 1	2,836	(5,124)				(2,287)
Equity-based compensation expense			6,183				6,183
Other, net of tax.				214			$ 214
Preferred stock ending balance, share at Jun. 30, 2018							0
Common stock ending balance, share at Jun. 30, 2018	46,034,000						46,033,516
Ending balance, value at Jun. 30, 2018	$ 460	$ (612,841)	$ 352,784	$ (129,325)	712,775	$ 7,811	$ 331,664
Cumulative Effect of New Accounting Principle in Period of Adoption					$ (6,584)		$ (6,584)