CONDENSED CONSOLIDATED STATEMENT OF CHANGES IN EQUITY - 9 months ended Sep. 30, 2018 - USD ($) $ in Thousands		Total	Common Stock	Treasury	Additional Paid-In Capital	Retained Earnings	Noncontrolling Interest Non Redeemable
Beginning balance, Amount at Dec. 31, 2017		$ 506,591	$ 226	$ (42,249)	$ 126,490	$ 364,401	$ 57,723
Beginning balance (in shares) at Dec. 31, 2017			22,640,046
Beginning balance, Treasury (in shares) at Dec. 31, 2017		(4,890,504)		(4,890,504)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	[1]	$ 46,330				43,022	3,308
Acquired noncontrolling interest		38,145					38,145
Noncontrolling interest distributions		(1,663)					(1,663)
NCI acquired, net of sales		10,253			5,041		5,212
Nonvested stock compensation		7,336			7,336
Restricted stock vesting		0	$ 2		(2)
Restricted stock vesting (in shares)			211,355
Treasury shares redeemed to pay income tax		$ (6,719)		$ (6,719)
Treasury shares redeemed to pay income tax (in shares)		(67,919)		(67,919)
Merger consideration		$ 795,405	$ 127		795,278
Merger consideration (in shares)			12,765,288
Issuance of common stock under Employee Stock Purchase Plan		1,016	$ 1		1,015
Issuance of common stock under Employee Stock Purchase Plan (in shares)			15,387
Ending balance, Amount at Sep. 30, 2018		$ 1,396,694	$ 356	$ (48,968)	$ 935,158	$ 407,423	$ 102,725
Ending balance (in shares) at Sep. 30, 2018			35,632,076
Ending balance, Treasury (in shares) at Sep. 30, 2018		(4,958,423)		(4,958,423)

[1] Net income excludes net income attributable to noncontrolling interest-redeemable of $7.3 million during the nine months ending September 30, 2018. Noncontrolling interest-redeemable is reflected outside of permanent equity on the condensed consolidated balance sheets. See Note 9 of the Notes to Condensed Consolidated Financial Statements.