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, 2012	$ 411	$ (41,012)	$ 317,534	$ (6,528)	$ 16,901	$ 287,306
BALANCE (in shares) at Dec. 31, 2012	41,123,365	(3,879,299)
Increase (Decrease) in Stockholders' Equity
Net income				27,269	1,287	28,556
Issuance of Stock:
Issuance of shares for options exercised including tax benefit		$ 4,711	522			5,233
Issuance of shares for options exercised including tax benefit (in shares)		439,762
Issuance of restricted stock		$ 1,301	(1,301)
Issuance of restricted stock (in shares)		122,375
Shares received in lieu of tax withholding payment on vested restricted stock		$ (631)				(631)
Shares received in lieu of tax withholding payment on vested restricted stock (in shares)		(45,266)
Tax benefit from vesting of restricted stock			184			184
Forfeiture of unvested restricted stock		$ (5)	5
Forfeiture of unvested restricted stock (in shares)		(469)
Stock-based compensation expense			3,041			3,041
Dividends			(1,862)	(5,973)		(7,835)
Share repurchase		$ (1,832)				(1,832)
Share repurchase (in shares)		(125,541)
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	(3,488,438)				37,578,000
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		$ 1,243	(1,243)
Issuance of restricted 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					(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	(3,853,586)				37,270,000
Increase (Decrease) in Stockholders' Equity
Net income				49,364	8,076	$ 57,440
Issuance of Stock:
Issuance of shares for options exercised including tax benefit		$ 3,728	966			4,694
Issuance of shares for options exercised including tax benefit (in shares)		317,333
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			3,057			3,057
Dividends				(9,358)		(9,358)
Distribution to noncontrolling interests					(4,904)	(4,904)
Share repurchase		$ (8,330)				$ (8,330)
Share repurchase (in shares)		(315,953)				(300,000)
BALANCE at Dec. 31, 2015	$ 411	$ (46,845)	$ 323,765	$ 69,390	$ 18,284	$ 365,005
BALANCE (in shares) at Dec. 31, 2015	41,123,365	(3,696,781)				37,427,000