CONDENSED CONSOLIDATED STATEMENT OF CHANGES IN EQUITY (Unaudited) - 9 months ended Sep. 30, 2017 - USD ($) $ in Thousands	Total	Common Stock	Treasury Stock	Additional Paid-In Capital	Retained Earnings	Noncontrolling Interest Non Redeemable
Beginning balance, Amount at Dec. 31, 2016	$ 401,552	$ 224	$ (39,135)	$ 119,748	$ 314,289	$ 6,426
Beginning balance, Shares at Dec. 31, 2016		22,429,041
Beginning balance, Treasury Shares at Dec. 31, 2016	(4,828,679)		(4,828,679)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	$ 31,350				31,678	(328)
Acquired noncontrolling interest	52,492					52,492
Noncontrolling Interest Distributions	(1,472)					(1,472)
Sale of noncontrolling interest	630			348		282
Purchase of additional controlling interest	(184)			(184)
Nonvested stock compensation	4,522			4,522
Issuance of vested stock		$ 2		(2)
Issuance of vested stock, Shares		191,463
Treasury shares redeemed to pay income tax	$ (3,091)		$ (3,091)
Treasury shares redeemed to pay income tax, Shares	(61,502)		(61,502)
Issuance of common stock under Employee Stock Purchase Plan	$ 776			776
Issuance of common stock under Employee Stock Purchase Plan, Shares		14,818
Ending balance, Amount at Sep. 30, 2017	$ 486,575	$ 226	$ (42,226)	$ 125,208	$ 345,967	$ 57,400
Ending balance, Shares at Sep. 30, 2017		22,635,322
Ending balance, Treasury Shares at Sep. 30, 2017	(4,890,181)		(4,890,181)