Goodwill and Specifically Identifiable Intangible Assets - Goodwill and Specifically Identifiable Intangible Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Goodwill [Roll Forward]
Gross goodwill as of beginning of year	$ 13,864	$ 13,864	$ 0
Goodwill resulting from business acquisition	0	0	13,864
Gross goodwill, before impairments	13,864	13,864	13,864
Accumulated impairment as of beginning of year	0	0	0
Current year impairments	0	0	0
Net goodwill as of end of year	$ 13,864	$ 13,864	$ 13,864