Lease Assets and Lease Liabilities Lease Assets and Lease Liabilities (Supplemental Cash Flow Information) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Leases [Abstract]
Operating cash flows from operating leases (1) (2)	$ 405	$ 436	$ 1,212	$ 1,373
Right-of-use assets obtained in exchange for new operating lease liabilities	$ 0	$ 12	$ 35,372	$ 197