Equity Investment - Summary of Financial Information for Matrix (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Schedule of Investments [Line Items]
Current assets	$ 256,427				$ 210,980				$ 256,427	$ 210,980
Current liabilities	150,186				142,883				150,186	142,883
Revenue	384,833	$ 393,385	$ 363,911	$ 367,815	360,762	$ 343,771	$ 343,736	$ 336,696
Operating (loss) income	7,554	16,987	(3,250)	3,441	(693)	9,435	3,431	12,103	24,732	24,276	$ 37,484
Net (loss) income	(6,058)	$ 8,154	$ (1,712)	$ 582	(20,350)	$ 7,154	$ (11,215)	$ 5,430	966	(18,981)	53,369
Matrix
Schedule of Investments [Line Items]
Current assets	64,221				61,565				64,221	61,565
Long-term assets	631,007				719,450				631,007	719,450
Current liabilities	31,256				27,619				31,256	27,619
Long-term liabilities	$ 351,380				$ 373,159				351,380	373,159
Revenue									275,391	282,067	227,872
Operating (loss) income									(61,000)	(1,186)	11,870
Net (loss) income									$ (69,353)	$ (19,962)	$ 26,665