Fair Value Measurements - Measurement Inputs (Details) - Significant Unobservable Inputs (Level 3) - Fair Value, Measurements, Nonrecurring $ in Thousands	Dec. 31, 2018 USD ($)
Impaired loans
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Fair Value	$ 21,686
OREO
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Fair Value	$ 4,319
Measurement Input, Price Volatility \| Minimum \| Impaired loans
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Debt instrument, measurement input	0.04
Measurement Input, Price Volatility \| Minimum \| OREO
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
OREO, measurement input	0.04
Measurement Input, Price Volatility \| Maximum \| Impaired loans
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Debt instrument, measurement input	0.10
Measurement Input, Price Volatility \| Maximum \| OREO
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
OREO, measurement input	0.10

Value of input used to measure debt instrument, including, but not limited to, convertible and non-convertible debt.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258

+ Details

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Balance Type:	na
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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

Fair value of financial and nonfinancial obligations.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258

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- Definition

Value of input used to measure real estate owned by financial institution by financial institution which is not directly related to its business.

+ References

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