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Investment Securities - Summary of Amortized Cost of Held-to-Maturity Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	$ 7,969,672	$ 8,444,362
Agency CMO
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	16,791	19,847
Agency MBS
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	2,767,869	3,109,411
Agency CMBS
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	4,295,308	4,357,505
Municipal bonds and notes
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	824,734	891,909
CMBS
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	64,970	65,690
Aaa
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	363,636	406,877
Aaa | Agency CMO
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	0	0
Aaa | Agency MBS
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	0	0
Aaa | Agency CMBS
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	0	0
Aaa | Municipal bonds and notes
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	298,666	341,187
Aaa | CMBS
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	64,970	65,690
Aa1
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	7,233,155	7,645,090
Aa1 | Agency CMO
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	16,791	19,847
Aa1 | Agency MBS
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	2,767,869	3,109,411
Aa1 | Agency CMBS
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	4,295,308	4,357,505
Aa1 | Municipal bonds and notes
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	153,187	158,327
Aa1 | CMBS
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	0	0
Aa2
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	234,269	230,986
Aa2 | Agency CMO
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	0	0
Aa2 | Agency MBS
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	0	0
Aa2 | Agency CMBS
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	0	0
Aa2 | Municipal bonds and notes
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	234,269	230,986
Aa2 | CMBS
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	0	0
Aa3
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	112,482	128,692
Aa3 | Agency CMO
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	0	0
Aa3 | Agency MBS
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	0	0
Aa3 | Agency CMBS
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	0	0
Aa3 | Municipal bonds and notes
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	112,482	128,692
Aa3 | CMBS
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	0	0
A1
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	9,539	13,761
A1 | Agency CMO
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	0	0
A1 | Agency MBS
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	0	0
A1 | Agency CMBS
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	0	0
A1 | Municipal bonds and notes
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	9,539	13,761
A1 | CMBS
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	0	0
Moody's, A2 Rating [Member]
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	4,165	0
Moody's, A2 Rating [Member] | Agency CMO
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	0	0
Moody's, A2 Rating [Member] | Agency MBS
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	0	0
Moody's, A2 Rating [Member] | Agency CMBS
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	0	0
Moody's, A2 Rating [Member] | Municipal bonds and notes
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	4,165	0
Moody's, A2 Rating [Member] | CMBS
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	0	0
A3
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	0	4,165
A3 | Agency CMO
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	0	0
A3 | Agency MBS
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	0	0
A3 | Agency CMBS
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	0	0
A3 | Municipal bonds and notes
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	0	4,165
A3 | CMBS
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	0	0
Not Rated
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	12,426	14,791
Not Rated | Agency CMO
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	0	0
Not Rated | Agency MBS
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	0	0
Not Rated | Agency CMBS
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	0	0
Not Rated | Municipal bonds and notes
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	12,426	14,791
Not Rated | CMBS
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	$ 0	$ 0

X

- Definition

Amount excluding accrued interest, before allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479344/326-20-45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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-Publisher FASB
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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-Section 50
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+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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