Loans and Allowance for Credit Losses - Loans modified in troubled debt restructurings (Details) $ in Thousands	3 Months Ended
Mar. 31, 2020 USD ($) contract	Mar. 31, 2019 USD ($) contract
Number of loans - restructured accruing \| contract	11	10
Number of loans - restructured nonaccruing \| contract	2	3
Number of loans \| contract	13	13
Restructured accruing	$ 17,872	$ 26,177
Restructured nonaccruing	2,507	538
Troubled Debt Restructured	20,379	26,715
Specific allowance	1,007	3,775
Commercial
Restructured accruing	1,438	3,218
Restructured nonaccruing	137	538
Troubled Debt Restructured	1,575	3,756
Specific allowance		775
Income Producing - Commercial Real Estate
Restructured accruing	15,574	19,622
Troubled Debt Restructured	15,574	19,622
Specific allowance	1,007	3,000
Owner Occupied - Commercial Real Estate
Restructured accruing	860	3,337
Restructured nonaccruing	2,370
Troubled Debt Restructured	$ 3,230	$ 3,337

Number of financing receivables outstanding that have been modified by troubled debt restructurings.

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- Definition

Post-modification amount of investment in financing receivables modified by troubled debt restructurings accruing.

+ References

No definition available.

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- Definition

Post-modification amount of investment in financing receivables modified by troubled debt restructurings nonaccruing.

+ References

No definition available.

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- Definition

Number of accruing financing receivables that have been modified by troubled debt restructurings.

+ References

No definition available.

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- Definition

Number of nonaccruing financing receivables that have been modified by troubled debt restructurings.

+ References

No definition available.

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- Definition

Amount of credit loss expense (reversal of expense) for financing receivable from change in methodology.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 11
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=119407570&loc=SL82919244-210447

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- Definition

Amount, after troubled debt restructuring, of modified financing receivable.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953676-111524

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