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Loans and Allowance for Loan Losses - Troubled Debt Restructuring Modifications (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018 USD ($) contract	Jun. 30, 2017 USD ($) contract	Jun. 30, 2018 USD ($) contract loan	Jun. 30, 2017 USD ($) contract loan	Dec. 31, 2017 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Contracts Modified | contract		0
Pre-Modification Outstanding Recorded Investment		$ 0
Post-Modification Outstanding Recorded Investment		0
Post-Modification Outstanding Recorded Investment at Period End		$ 0
Number of modified TDR loans that defaulted | loan			0	0
Purchased Credit-impaired (PCI) loans accreting interest	$ 2,100		$ 2,100		$ 2,100
Commercial loans | Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Contracts Modified | contract	2		2
Pre-Modification Outstanding Recorded Investment	$ 254		$ 254
Post-Modification Outstanding Recorded Investment	245		245
Post-Modification Outstanding Recorded Investment at Period End	$ 235		$ 235
Consumer loans | Installment and other consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Contracts Modified | contract				1
Pre-Modification Outstanding Recorded Investment				$ 50
Post-Modification Outstanding Recorded Investment				50
Post-Modification Outstanding Recorded Investment at Period End				$ 49

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The carrying balance of certain loans acquired with evidence of deteriorated credit quality and currently accreting interests.

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

+ References

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-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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-Name Accounting Standards Codification
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