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Commitments and Contingencies (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
--- | --- | --- | ---
Guarantor Obligations [Line Items] |  |  |
Amortization Method Qualified Affordable Housing Project Investments | $ 163,900 | $ 167,800 |
FDIC shared-loss payable | 15,601 | 112,395 | $ 105,618
Commitments to Extend Credit |  |  |
Guarantor Obligations [Line Items] |  |  |
Unused Commitments to Extend Credit | 12,098,417 | 10,682,378 |
Amortization Method Qualified Affordable Housing Project Investments | 53,700 | 70,000 |
Standby Letters of Credit |  |  |
Guarantor Obligations [Line Items] |  |  |
Affordable Housing Program Obligation | $ 129,819 | $ 99,601 |

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- Definition Amount of commitment or contingent commitments to qualified affordable housing project investments. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 740 -Section 50 -Paragraph 2 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=116633289&loc=SL49122993-202985 + Details
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