Summary of Significant Accounting Policies and Other Information - Schedule of Prior Period Adjustment (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		9 Months Ended		12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Jun. 30, 2018	Jun. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2018	Dec. 31, 2017	Jan. 01, 2018
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Other accrued liabilities	$ 38,697	$ 28,809	$ 41,884	$ 30,110	$ 44,762	$ 37,295	$ 45,700	$ 34,332	$ 33,626
Total current liabilities	130,580	112,893	194,340	111,012	229,951	132,842	220,631	122,612
Other noncurrent liabilities	15,311	19,753	15,753	17,707	16,612	17,410	32,470	12,393
Accrued expenses	4,757	1,861	7,914	3,826	10,773	10,622	11,630	7,839
Other noncurrent liabilities	$ 2,902	450	$ 2,000	(1,478)	$ 2,901	(2,576)	$ 18,786	(7,070)
Previously Reported
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Other accrued liabilities		35,234		35,379		41,393		38,362
Total current liabilities		119,318		116,281		136,940		126,654
Other noncurrent liabilities		13,328		12,438		13,312		8,351
Accrued expenses		2,432		3,242		8,867		6,029
Other noncurrent liabilities		(121)		(894)		(821)		(5,260)
Adjustment
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Other accrued liabilities		(6,425)		(5,269)		(4,098)		(4,042)
Total current liabilities		(6,425)		(5,269)		(4,098)		(4,042)
Other noncurrent liabilities		6,425		5,269		4,098		4,042
Accrued expenses		(571)		584		1,755		1,810
Other noncurrent liabilities		571		(584)		(1,755)		(1,810)
As Revised
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Other accrued liabilities		28,809		30,110		37,295		34,320
Total current liabilities		112,893		111,012		132,842		122,612
Other noncurrent liabilities		$ 19,753		$ 17,707		$ 17,410		$ 12,393