CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Common Stock	Additional Paid-in Capital	Retained Earnings	Non Controlling Interest	Total
Balance at Dec. 31, 2013	$ 5	$ 159,196	$ 238,216	$ 1,031	$ 398,448
Balance (in shares) at Dec. 31, 2013	51,571,394
Increase (Decrease) in Stockholders' Equity Roll Forward
Net income			63,156	526	63,682
Issuance of shares to employees and directors		2,897			2,897
Issuance of shares to employees and directors (in shares)	90,002
Amortization of Restricted Stock Units		934			934
Dividend equivalent Units accrued - Restricted Stock Units		3	(3)
Repurchase of stock		(2,844)			(2,844)
Repurchase of stock (in shares)	(100,000)
Distribution of non-controlling entities				(1,590)	(1,590)
Dividends			(7,741)		(7,741)
Balance at Dec. 31, 2014	$ 5	160,186	293,628	(33)	453,786
Balance (in shares) at Dec. 31, 2014	51,561,396
Increase (Decrease) in Stockholders' Equity Roll Forward
Net income			36,872	279	37,151
Issuance of shares to employees and directors		2,096			2,096
Issuance of shares to employees and directors (in shares)	114,744
Amortization of Restricted Stock Units		1,050			1,050
Dividend equivalent Units accrued - Restricted Stock Units		12	(12)
Distribution of non-controlling entities				(29)	(29)
Dividends			(10,589)		(10,589)
Balance at Dec. 31, 2015	$ 5	163,344	319,899	217	483,465
Balance (in shares) at Dec. 31, 2015	51,676,140
Increase (Decrease) in Stockholders' Equity Roll Forward
Net income			26,723	1,002	27,725
Issuance of shares to employees and directors		2,133			2,133
Issuance of shares to employees and directors (in shares)	108,102
Amortization of Restricted Stock Units		1,627			1,627
Dividend equivalent Units accrued - Restricted Stock Units		23	(23)
Repurchase of stock		(4,999)			(4,999)
Repurchase of stock (in shares)	(207,800)
Dividends			(11,381)		(11,381)
Balance at Dec. 31, 2016	$ 5	$ 162,128	$ 335,218	$ 1,219	$ 498,570
Balance (in shares) at Dec. 31, 2016	51,576,442
Increase (Decrease) in Stockholders' Equity Roll Forward
Dividend equivalent Units accrued – Restricted Stock Units					1,693