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Investment Securities - Summary of Held to Maturity Debt Securities by Stated Maturity (Detail) $ in Thousands | Sep. 30, 2023 USD ($)
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Schedule of Held-to-Maturity Securities [Line Items] |
Amortized Cost | $ 1,178,370
Fair Value | 1,115,576
Asset-backed securities |
Schedule of Held-to-Maturity Securities [Line Items] |
Amortized Cost | 645,362
Fair Value | 640,188
Agency-guaranteed residential mortgage-backed securities |
Schedule of Held-to-Maturity Securities [Line Items] |
Amortized Cost | 7,077
Fair Value | 6,050
Agency-guaranteed commercial mortgage-backed securities |
Schedule of Held-to-Maturity Securities [Line Items] |
Amortized Cost | 1,870
Fair Value | 1,731
Agency-guaranteed residential collateralized mortgage obligations |
Schedule of Held-to-Maturity Securities [Line Items] |
Amortized Cost | 191,469
Fair Value | 168,138
Agency-guaranteed commercial collateralized mortgage obligations |
Schedule of Held-to-Maturity Securities [Line Items] |
Amortized Cost | 147,414
Fair Value | 131,566
Private label collateralized mortgage obligations |
Schedule of Held-to-Maturity Securities [Line Items] |
Amortized Cost | 185,178
Fair Value | $ 167,903

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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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