Fair Value Measurements Changes in Assets and Liabilities Measured at Fair Value on a Recurring Basis Using Level 3 Inputs (Details) - Fair Value, Measurements, Recurring - Level 3 - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Single-issuer trust preferred securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	$ 0	$ 2,400
Sales	0	(2,160)
Unrealized adjustment to fair value	0	(242)
Discount accretion	0	2
Balance, end of period	0	0
Auction rate securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	98,206	101,926
Sales	(24,619)	0
Unrealized adjustment to fair value	1,080	(3,720)
Discount accretion	0	0
Balance, end of period	$ 74,667	$ 98,206