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Loans - Narrative, Loans Held-for-Investment (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2022	Dec. 31, 2021
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held-for-sale	$ 2,346	$ 0
PCI loans	$ 4,111,857	$ 3,806,617
Home equity loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of PCI loans	13.00%
Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of PCI loans	25.00%	25.00%
Commercial and industrial loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of PCI loans	51.00%	48.00%
One-to-four family residential mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of PCI loans	11.00%	16.00%
Construction and land and home equity loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of PCI loans		11.00%
PCD loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
PCI loans	$ 13,136	$ 15,819

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Percentage of Purchase Credit Impaired Loans.

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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/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (b)
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-Publisher FASB
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- Definition

Amount, before valuation allowance, of financing receivable classified as held-for-sale.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
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