Interest Expense Components of Interest Expense (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Interest Expense [Abstract]
Interest Expense, Borrowings		$ 7,524	$ 9,304	$ 15,569	$ 19,015
Amortization of Debt Discount (Premium)	[1]	201	183	397	363
Amortization of Debt Issuance Costs		1,513	644	2,140	1,385
Interest Paid, Capitalized, Investing Activities		(702)	(1,075)	(1,390)	(2,229)
Interest Expense		$ 8,536	$ 9,056	16,716	$ 18,534
Accelerated Deferred Debt Issuance Cost				$ 900

[1] Attributable to the Second Lien Facility (see Note 7).