Loans and Allowance for Credit Losses on Loans - Loans Held for Investment by Portfolio Segment (Details) - USD ($) $ in Thousands	Jun. 30, 2025	Dec. 31, 2024	Jun. 30, 2024	Dec. 31, 2023
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 24,026,194	$ 22,542,823
Unearned income (net of direct origination costs)	(100,660)	(92,757)
Total loans held for investment	23,925,534	22,450,066
Allowance for credit losses on loans	(277,648)	(271,709)	$ (267,297)	$ (249,973)
Loans held for investment, net	23,647,886	22,178,357
Interest receivable	101,900	107,300
Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	11,930,668	11,145,591
Allowance for credit losses on loans	(207,912)	(198,423)	(180,354)	(171,437)
Mortgage finance
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	5,889,589	5,215,574
Allowance for credit losses on loans	(10,630)	(2,755)	(5,618)	(4,173)
Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	5,665,100	5,616,282
Allowance for credit losses on loans	(57,296)	(68,825)	(78,638)	(71,829)
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	540,837	565,376
Allowance for credit losses on loans	$ (1,810)	$ (1,706)	$ (2,687)	$ (2,534)

Financing Receivable Excluding Accrued Interest Before Allowance for Credit Loss, Net of Deferred Income

No definition available.

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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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
-SubTopic 20
-Name Accounting Standards Codification
-Section 40
-Paragraph 7
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481628/310-20-40-7

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481990/310-10-45-2

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- Definition

Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

+ References

+ Details

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- Definition

Amount of fee received for commitment to originate or purchase financing receivable where likelihood of commitment being exercised is remote, to be recognized as service income.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481598/310-20-45-2

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- Definition

Amortized cost excluding accrued interest, after allowance for credit loss, of financing receivable. Excludes net investment in lease.

+ References

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- Definition

Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease.

+ 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
-Section 50
-Paragraph 3B
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-URI https://asc.fasb.org/1943274/2147479319/326-20-50-3B

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-5

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- Definition

Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(3)(a)(4))
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-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 946
-SubTopic 310
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477802/946-310-45-1

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