Long-Term Debt - Schedule of Interest Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Debt Disclosure [Abstract]
Coupon interest at 3.75%	$ 12,188	$ 12,188	$ 12,188
Amortization of debt issuance costs	1,424	1,424	1,424
Total interest expense on Notes	$ 13,612	$ 13,612	$ 13,612