Supplemental Selected Quarterly Financial Data (Unaudited) - Schedule of Quarterly Financial Data (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Quarterly Financial Information Disclosure [Abstract]
Revenues	$ 247,664	$ 235,329	$ 236,262	$ 227,293	$ 204,389	$ 201,663	$ 183,020	$ 158,691	$ 946,548	$ 747,763	$ 471,496
Operating Income	20,523	10,054	19,143	13,838	9,840	9,882	7,968	3,746	63,558	31,436	(57,213)
Income from continuing operations	10,569	3,644	10,846	7,222	7,917	2,653	1,632	(983)	32,281	11,219	(40,712)
Net income	$ 10,569	$ 3,644	$ 10,846	$ 7,222	$ (9,450)	$ 2,653	$ 1,632	$ (983)	$ 32,281	$ (6,148)	$ (40,712)
Income (loss) per common share - basic:
Income (loss) from continuing operations, basic (in dollars per share)	$ 0.12	$ 0.04	$ 0.12	$ 0.08	$ 0.09	$ 0.03	$ 0.02	$ (0.01)	$ 0.36	$ 0.13	$ (0.49)
Net income (loss), basic (in dollars per share)	0.12	0.04	0.12	0.08	(0.11)	0.03	0.02	(0.01)	0.36	(0.07)	(0.49)
Income (loss) per common share - diluted:
Income (loss) from continuing operations, diluted (in dollars per share)	0.11	0.04	0.12	0.08	0.09	0.03	0.02	(0.01)	0.35	0.13	(0.49)
Net income (loss), diluted (in dollars per share)	$ 0.11	$ 0.04	$ 0.12	$ 0.08	$ (0.11)	$ 0.03	$ 0.02	$ (0.01)	$ 0.35	$ (0.07)	$ (0.49)