Loans - Narrative, PCI Loans (Details) - USD ($)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amount of loans held for sale	$ 0	$ 0
PCI loans held-for-investment	3,437,085,000	3,245,170,000
Principal balance of loans on non accrual status	$ 2,600,000	$ 3,200,000
Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Purchased credit-impaired (PCI) loan percent	29.00%	27.00%
Commercial and Industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Purchased credit-impaired (PCI) loan percent	42.00%	50.00%
PCI
Accounts, Notes, Loans and Financing Receivable [Line Items]
PCI loans held-for-investment	$ 17,365,000	$ 20,143,000
Minimum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Principal balance of loans on non accrual status	$ 500,000

Percentage of Purchase Credit Impaired Loans.

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- Definition

Principal balance threshold for non accrual status.

+ References

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- Definition

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+ References

No definition available.

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- Definition

Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4428-111522

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5074-111524

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- Definition

The face amount of loans that will be sold to other entities.

+ References

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