Loans and Allowance for Credit Losses - Schedule of Outstanding Contractually Required Principal and Interest and Carrying Amount of PCI Loans Receivable (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding contractually required principal and interest		$ 14,692
Gross loans	$ 4,852,911	4,194,512
Real Estate Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding contractually required principal and interest		14,015
Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding contractually required principal and interest		677
Gross loans	$ 1,536,903	1,342,683
Purchased Credit Impaired Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans		12,675
Purchased Credit Impaired Loans \| Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans		$ 550

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.

No definition available.

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- Definition

The undiscounted sum of all amounts, including amounts deemed principal, interest, fees, penalties, and other under the loan, owed to the investor at the reporting date, whether or not currently due and whether or not any such amounts have been written or charged off by the investor. This relates to loans not accounted for as debt securities, with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 15
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=118938799&loc=d3e13503-111538

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=118939070&loc=d3e15032-111544

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- Definition

Amount, before allowance for credit loss, of financing receivable.

+ 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)
-URI http://asc.fasb.org/extlink&oid=119407570&loc=SL82919230-210447

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