CONSOLIDATED STATEMENTS OF EQUITY - USD ($) shares in Thousands, $ in Thousands	Total	Common stock	Additional paid-in capital	Retained earnings	Accumulated other comprehensive loss	Treasury stock, at cost	Non-controlling interests
Balance at Dec. 31, 2013	$ 157,741	$ 25,413	$ 89,273	$ 239,561	$ 0	$ (197,548)	$ 1,042
Balance (in shares) at Dec. 31, 2013		25,413
Increase (Decrease) in Equity
Net income	137,087			134,484			2,603
Other comprehensive loss, net of tax	0
Distributions to non-controlling interest holders	(2,596)						(2,596)
Share-based compensation expense	2,236		2,236
Exercise of stock options	2,688			(6,078)		8,766
Repurchase of shares	(255,713)					(255,713)
Balance at Dec. 31, 2014	41,443	$ 25,413	91,509	367,967	0	(444,495)	1,049
Balance (in shares) at Dec. 31, 2014		25,413
Increase (Decrease) in Equity
Net income	44,800			41,598			3,202
Other comprehensive loss, net of tax	0
Distributions to non-controlling interest holders	(2,959)						(2,959)
Share-based compensation expense	4,812		4,812
Exercise of stock options	1,390			(8,292)		9,682
Issuance of restricted shares for acquisitions	21,733			(32,003)		53,736
Repurchase of shares	(58,949)					(58,949)
Balance at Dec. 31, 2015	52,270	$ 25,413	96,321	369,270	0	(440,026)	1,292
Balance (in shares) at Dec. 31, 2015		25,413
Increase (Decrease) in Equity
Net income	31,386			28,693			2,693
Other comprehensive loss, net of tax	(1,745)				(1,745)
Distributions to non-controlling interest holders	(2,580)						(2,580)
Share-based compensation expense	6,188		6,188
Excess tax benefit on stock-based compensation	4,779		4,779
Exercise of stock options	9,558			(64,177)		73,735
Repurchase of shares	(37,662)					(37,662)
Balance at Dec. 31, 2016	$ 62,194	$ 25,413	$ 107,288	$ 333,786	$ (1,745)	$ (403,953)	$ 1,405
Balance (in shares) at Dec. 31, 2016		25,413