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Investment Securities - Summary of Held-to-Maturity Debt Securities by Stated Maturity (Detail) $ in Thousands | Mar. 31, 2024 USD ($)
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Schedule of Held-to-Maturity Securities [Line Items] |
Amortized Cost | $ 1,032,037
Fair Value | 972,628
Asset-backed securities |
Schedule of Held-to-Maturity Securities [Line Items] |
Amortized Cost | 509,690
Fair Value | 507,603
Agency-guaranteed residential mortgage-backed securities |
Schedule of Held-to-Maturity Securities [Line Items] |
Amortized Cost | 7,001
Fair Value | 5,914
Agency-guaranteed commercial mortgage-backed securities |
Schedule of Held-to-Maturity Securities [Line Items] |
Amortized Cost | 1,830
Fair Value | 1,679
Agency-guaranteed residential collateralized mortgage obligations |
Schedule of Held-to-Maturity Securities [Line Items] |
Amortized Cost | 182,856
Fair Value | 162,133
Agency-guaranteed commercial collateralized mortgage obligations |
Schedule of Held-to-Maturity Securities [Line Items] |
Amortized Cost | 146,001
Fair Value | 124,466
Private label collateralized mortgage obligations |
Schedule of Held-to-Maturity Securities [Line Items] |
Amortized Cost | 184,659
Fair Value | $ 170,833

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- Definition Amount excluding accrued interest, after allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity) without single maturity date and not allocated over maturity grouping. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Subparagraph (f) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481800/320-10-50-5 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 942 -SubTopic 320 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480832/942-320-50-3 + Details
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