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Investment Securities - Summary of Amortized Cost of Held-to-Maturity Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	$ 8,444,362	$ 7,074,797
Agency CMO
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	19,847	23,470
Agency MBS
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	3,109,411	2,409,521
Agency CMBS
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	4,357,505	3,625,627
Municipal bonds and notes
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	891,909	916,104
CMBS
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	65,690	100,075
Aaa
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	406,877	433,554
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	341,187	333,479
Aaa | CMBS
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	65,690	100,075
Aa1
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	7,645,090	6,221,233
Aa1 | Agency CMO
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	19,847	23,470
Aa1 | Agency MBS
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	3,109,411	2,409,521
Aa1 | Agency CMBS
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	4,357,505	3,625,627
Aa1 | Municipal bonds and notes
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Total held-to-maturity	158,327	162,615
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	230,986	253,671
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	230,986	253,671
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	128,692	115,404
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	128,692	115,404
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	13,761	32,732
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	13,761	32,732
A1 | 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	4,165	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	4,165	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	14,791	14,038
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	14,791	14,038
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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-Name Accounting Standards Codification
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-3B

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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-Section 50
-Paragraph 5
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-Publisher FASB
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+ References

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