CONDENSED CONSOLIDATED STATEMENT OF CHANGES IN EQUITY - USD ($) $ in Thousands	Total	Common Stock [Member]	Treasury [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Non-controlling Interest Non Redeemable [Member]	Total Equity [Member]	Non-Controlling Interest - Redeemable [Member]	Net Income (Loss) [Member]
Balances, Amount at Dec. 31, 2014		$ 220	$ (35,660)	$ 108,708	$ 245,371	$ 2,956	$ 321,595	$ 11,517
Balances, Shares at Dec. 31, 2014		22,015,211	4,734,363
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income					32,335	1,737	34,072	7,578
Income from continuing operations	$ 41,650								$ 41,650
Noncontrolling interest acquired						155	155	0
Noncontrolling interest distributions						(1,637)	(1,637)	(6,687)
Stock options exercised, Shares		9,500
Stock options exercised				144			144
Purchase of additional controlling interest				275			275
Nonvested Stock Compensation				4,225			4,225
Issuance of vested stock, shares		176,989
Treasury shares redeemed to pay income tax			$ (1,479)				(1,479)
Treasury shares redeemed to pay income tax, shares	(42,197)		(42,197)
Excess tax benefits-vesting nonvested stock				211			211
Issuance of common stock under Employee Stock Purchase Plan		$ 2		780			782
Shares Issued during Period (Shares)	22,723	22,723
Balances, Amount at Dec. 31, 2015		$ 222	$ (37,139)	113,793	277,706	3,211	357,793	12,408
Balances, Shares at Dec. 31, 2015		22,224,423	4,776,560
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income					36,583	1,373	37,956	7,986
Income from continuing operations	$ 45,942								$ 45,942
Noncontrolling interest acquired						1,783	1,783
Noncontrolling interest distributions						(1,341)	(1,341)	(7,827)
Stock options exercised, Shares		5,500
Stock options exercised				109			109
Sale of noncontrolling interest				(931)		1,400	469
Nonvested Stock Compensation				4,872			4,872
Issuance of vested stock				(2)
Issuance of vested stock, shares		174,969
Treasury shares redeemed to pay income tax			$ (1,996)				(1,996)
Treasury shares redeemed to pay income tax, shares	(52,119)		(52,119)
Excess tax benefits-vesting nonvested stock				995			995
Issuance of common stock under Employee Stock Purchase Plan		$ 0		912			912
Shares Issued during Period (Shares)	24,149	24,149
Balances, Amount at Dec. 31, 2016	$ 401,552	$ 224	$ (39,135)	119,748	314,289	6,426	401,552	12,567
Balances, Shares at Dec. 31, 2016		22,429,041	4,828,679
Ending Balance, Treasury Shares at Dec. 31, 2016	(4,828,679)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income					50,112	(595)	49,517	10,869
Income from continuing operations	$ 60,386
Noncontrolling interest acquired						53,657	53,657
Noncontrolling interest distributions						(2,047)	(2,047)	(9,335)
Purchase of additional controlling interest				368			368	1,120
Sale of noncontrolling interest				122		282	404	412
Nonvested Stock Compensation				5,964			5,964
Issuance of vested stock		$ 2		(2)
Issuance of vested stock, shares		192,463
Treasury shares redeemed to pay income tax			$ (3,114)				(3,114)
Treasury shares redeemed to pay income tax, shares	(61,825)		(61,825)
Issuance of common stock under Employee Stock Purchase Plan				1,026			1,026
Shares Issued during Period (Shares)	18,542	18,542
Balances, Amount at Dec. 31, 2017	$ 506,591	$ 226	$ (42,249)	$ 126,490	$ 364,401	$ 57,723	$ 506,591	$ 13,393
Balances, Shares at Dec. 31, 2017		22,640,046	4,890,504
Ending Balance, Treasury Shares at Dec. 31, 2017	(4,890,504)