Loans, Allowance for Loan Losses, and Credit Quality - Narrative (Details)	9 Months Ended	12 Months Ended
Sep. 30, 2019 USD ($) Loan	Dec. 31, 2018 USD ($) Loan
Loans and Leases Receivable Disclosure [Line Items]
Remaining impaired loans	$ 12,738,000	$ 9,939,000
Number of loans classified as troubled debt \| Loan	5	4
Troubled debt restructuring current outstanding balance	$ 1,200,000	$ 600,000
Pre-modification balance	1,400,000	2,700,000
Acquired
Loans and Leases Receivable Disclosure [Line Items]
PCI loans acquired fair value	43,600,000
Nonaccretable mark	34,400,000
Accretable mark	0
Remaining impaired loans	8,251,000	$ 9,391,000
Current
Loans and Leases Receivable Disclosure [Line Items]
Troubled debt restructuring current outstanding balance	$ 500,000

Represents fair value of purchase credit impaired loans.

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- Definition

The aggregate excess of a loan's cash flows expected to be collected over the investor's initial investment in the loan. This relates to loans with deteriorating 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

No definition available.

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- Definition

The amount of the loan's contractually required payments receivable in excess of the amount of its cash flows expected to be collected. This relates to loans with deteriorating 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

No definition available.

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953676-111524

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- Definition

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

+ References

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- Definition

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

+ References

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- Definition

Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953550-111524

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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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