Goodwill and Intangible Assets - Finite-lived Intangible Assets Roll Forward (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Finite-lived Intangible Assets, Gross [Roll Forward]
Intangible assets, beginning of period	$ 35,240	$ 35,240	$ 35,240
Additions	0
Total intangible assets, end of period	35,240		35,240
Accumulated Amortization [Roll Forward]
Accumulated amortization, January 1	(32,055)	(29,985)	(29,985)
Current year amortization	(380)	$ (516)	(2,070)
Total accumulated amortization	(32,435)		(32,055)
Net intangible assets
Net intangible assets, end of year	2,805		3,185
Infinite-lived intangible assets	6,892		6,892
Total net intangible assets	$ 9,697		$ 10,077