Commitments and Contingencies Commitments and Contingencies - Credit Losses on Off-Balance-Sheet Commitments (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Off-Balance Sheet, Credit Loss, Liability	$ 46,939	$ 500	$ 500	$ 500
Impact of adopting ASC 326	0	0	39,377	0
Credit loss expense (benefit)	(3,276)	0	3,786	0
Off-Balance Sheet, Credit Loss, Liability	$ 43,663	$ 500	$ 43,663	$ 500