CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Common Stock	Treasury Stock	Additional Paid-In Capital	Retained Earnings	Non-Controlling Interests	Total
BALANCE at Dec. 31, 2013	$ 411	$ (37,468)	$ 318,123	$ 14,768	$ 18,188	$ 314,022
BALANCE (in shares) at Dec. 31, 2013	41,123,365
BALANCE (in shares) at Dec. 31, 2013		(3,488,438)
Increase (Decrease) in Stockholders' Equity
Net income				23,063	5,536	28,599
Issuance of Stock:
Issuance of shares for options exercised including tax benefit		$ 1,132	79			1,211
Issuance of shares for options exercised including tax benefit (in shares)		103,619
Issuance of restricted stock & performance stock		$ 1,243	(1,243)
Issuance of restricted stock & performance stock (in shares)		115,044
Shares received in lieu of tax withholding payment on vested restricted stock		$ (531)				(531)
Shares received in lieu of tax withholding payment on vested restricted stock (in shares)		(34,657)
Tax benefit from vesting of restricted stock			133			133
Stock-based compensation expense			2,992			2,992
Dividends				(8,447)		(8,447)
Distribution to noncontrolling interests (unaudited)					(8,612)	(8,612)
Share repurchase		$ (7,974)				(7,974)
Share repurchase (in shares)		(549,154)
BALANCE at Dec. 31, 2014	$ 411	$ (43,598)	320,084	29,384	15,112	$ 321,393
BALANCE (in shares) at Dec. 31, 2014	41,123,365					41,123,365
BALANCE (in shares) at Dec. 31, 2014		(3,853,586)				3,853,586
Increase (Decrease) in Stockholders' Equity
Net income				36,143	6,414	$ 42,557
Issuance of Stock:
Issuance of shares for options exercised including tax benefit		$ 2,983	451			3,434
Issuance of shares for options exercised including tax benefit (in shares)		256,983
Issuance of restricted stock & performance stock		$ 2,292	(626)			1,666
Issuance of restricted stock & performance stock (in shares)		200,015
Shares received in lieu of tax withholding payment on vested restricted stock		$ (937)				(937)
Shares received in lieu of tax withholding payment on vested restricted stock (in shares)		(44,590)
Tax benefit from vesting of restricted stock			284			284
Stock-based compensation expense			2,591			2,591
Dividends				(6,924)		(6,924)
Distribution to noncontrolling interests (unaudited)					(2,897)	(2,897)
Share repurchase		$ (4,930)				$ (4,930)
Share repurchase (in shares)		(195,833)				(200,000)
BALANCE at Sep. 30, 2015	$ 411	$ (44,190)	$ 322,784	$ 58,603	$ 18,629	$ 356,237
BALANCE (in shares) at Sep. 30, 2015	41,123,365					41,123,365
BALANCE (in shares) at Sep. 30, 2015		(3,637,011)				3,637,011