SUPPLEMENTARY FINANCIAL DATA (UNAUDITED) (Details) - USD ($) $ / shares in Units, $ in Thousands						3 Months Ended	12 Months Ended
Jul. 24, 2015	Apr. 24, 2015	Feb. 20, 2015	Oct. 16, 2014	Jul. 25, 2014	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
SUPPLEMENTARY FINANCIAL DATA (UNAUDITED)
Net revenue						$ 43,612	$ 33,309	$ 32,472	$ 24,176	$ 22,836	$ 13,562	$ 10,655	$ 6,896	$ 133,569	$ 53,949	$ 8,433
Total operating expenses						(5,596)	(5,391)	(6,595)	(6,644)	(5,543)	(5,128)	(5,547)	(6,151)	(24,581)	(22,369)	(42,362)
Income from operations						38,016	27,918	25,877	17,532	17,293	8,434	5,108	745	108,988	31,580	(33,929)
Net income (loss)						$ 25,883	$ 15,033	$ 14,597	$ 4,435	$ 4,301	$ (4,584)	$ (7,810)	$ (10,667)	$ 59,536	$ (18,760)	$ (168,464)
Basic and diluted net income (loss) per share						$ 0.24	$ 0.14	$ 0.13	$ 0.04	$ 0.04	$ (0.04)	$ (0.07)	$ (0.09)
Cash dividends declared per common share (in dollars per share)	$ 0.25	$ 0.25	$ 0.25	$ 0.25	$ 0.25	$ 0.00	$ 0.00	$ 0.00	$ 0.00	$ 0.00	$ 0.25	$ 0.25	$ 0.25	$ 0.00	$ 0.75	$ 0.50

Aggregate dividends declared during the period for each share of common stock outstanding.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=64863997&loc=d3e1377-109256

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
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