Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2020	Jan. 01, 2020	Dec. 31, 2019
Preferred shares, par value	$ 1.00		$ 1.00
Common shares, par value	$ 0.01		$ 0.01
Allowance for Unfunded Commitments	$ 57,276		$ 21,907
Retained Earnings (Accumulated Deficit)	2,424,992		2,380,867
Accounting Standards Update 2016-13
Retained Earnings (Accumulated Deficit)		$ 98,000
Deferred Income Tax Assets, Net		33,000
Cumulative Effect, Period Of Adoption, Adjustment \| Accounting Standards Update 2016-13
Allowance for Unfunded Commitments		18,690
SEC Schedule, 12-09, Reserve, Off-balance Sheet Activity [Member]
Allowance for Unfunded Commitments	$ 57,276		$ 21,907
SEC Schedule, 12-09, Reserve, Off-balance Sheet Activity [Member] \| Cumulative Effect, Period Of Adoption, Adjustment \| Accounting Standards Update 2016-13
Allowance for Unfunded Commitments		$ 18,690

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