Commitments and Contingencies - Summary of Contractual Amounts of Financial Instruments with Off-Balance-Sheet Risk (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2020	Dec. 31, 2019
Unused lines of credit
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Fixed Rate	$ 88,571	$ 89,040
Variable Rate	649,618	701,326
Total	738,189	790,366
Standby letters of credit
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Fixed Rate	7,098	7,119
Variable Rate	46,165	48,750
Total	53,263	55,869
Mortgage loan commitments
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Fixed Rate	156,421	48,999
Variable Rate	0	0
Total	$ 156,421	$ 48,999

Loans And Leases Receivable, Commitments

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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

No definition available.

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- Definition

Reflects the amount of cash required to fully fund agreements to provide advances to borrowers and lessees at stated interest rates.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 825
-Section 50
-Paragraph 1
-Subparagraph (b)(2)
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- Definition

Reflects the amount of cash required to fully fund agreements to provide advances to borrowers and lessees at interest rates that increase or decrease depending on certain facts or circumstances.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 825
-Section 50
-Paragraph 2
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