Investments in Qualified Affordable Housing Partnerships, Tax Credit and Other Investments, Net and Variable Interest Entities (Estimated Unfunded Commitments) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Investments in Tax Credit and Other Investments, Net [Line Items]
Unrealized gain (loss) recognized on marketable equity securities held	$ 789	$ (547)
Unfunded commitments related to investments in qualified affordable housing partnerships, tax credit and other investments
2020	121,875
2021	32,039
2022	13,459
2023	15,753
2024	8,145
Thereafter	2,538
Total	193,809
Investments in tax credit and other investments, net
Investments in Tax Credit and Other Investments, Net [Line Items]
Marketable equity securities	$ 31,700	$ 31,200

[Line Items] for Investments in Tax Credit and Other Investments, Net [Table]

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