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Fair Value of Financial Instruments - Additional Information (Details) - USD ($) $ in Thousands | 3 Months Ended
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Mar. 31, 2022 | Mar. 31, 2021
Securities |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fair value option elected aggregate carrying amount, asset | $ 5,000 | $ 22,000
Residential loans |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fair value option elected aggregate carrying amount, asset | 2,120,000 | 3,100,000
Business purpose loans |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fair value option elected aggregate carrying amount, asset | 920,000 | $ 386,000
Acquisitions | 64,875 |
HEIs |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Acquisitions | 40,000 |
MSRs |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Acquisitions | 5,793 |
Excess MSR |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fair value option elected aggregate carrying amount, asset | $ 5,000 |

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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Amount of purchases of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258 + Details
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