Loans and Allowance for Credit Losses - Industry Classification System (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Lessors of nonresidential buildings
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding Principal Balances	$ 3,655,366
Unfunded Commitments	916,186
Total exposure	4,571,552	$ 4,578,116
Lessors of residential buildings
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding Principal Balances	1,158,042
Unfunded Commitments	795,259
Total exposure	1,953,301	1,599,837
New Housing For-Sale Builders
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding Principal Balances	479,532
Unfunded Commitments	613,518
Total exposure	1,093,050	1,090,603
Hotels (except Casino Hotels) and Motels
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding Principal Balances	910,857
Unfunded Commitments	127,623
Total exposure	$ 1,038,480	$ 967,771