Investment Securities - Qualified Affordable Housing Projects (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Investments in Affordable Housing Projects [Abstract]
Investments in qualified affordable housing projects, net	$ 616,188	$ 458,476
Other liabilities	370,208	302,031
Tax credits and other tax benefits recognized	56,969	35,037	$ 24,047
Amortization expense included in provision for income taxes	$ 43,875	$ 28,267	$ 18,876

Amount of affordable housing tax credits and other tax benefits recognized.

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-Topic 323
-SubTopic 740
-Section 50
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Amount of investment in qualified affordable housing projects.

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Amount of amortization expense of investment in qualified affordable housing projects.

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Amount of commitment or contingent commitments to qualified affordable housing project investments.

+ References

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-Name Accounting Standards Codification
-Topic 323
-SubTopic 740
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