Acquired Loans - Components of the Allowance for Loan Losses on Acquired Loans (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period	$ 11,397	$ 11,992	$ 12,059
Provision for loan losses, acquired loans	(7,395)	3,757	3,425
Loans charged-off		(6,616)	(7,200)
Recoveries	77	2,264	3,708
Net (charge-offs) recoveries	77	(4,352)	(3,492)
Balance at end of period	$ 4,079	$ 11,397	$ 11,992

Allowance for loan and lease loss recovery and write off.

No definition available.

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Period Type:	duration

- Definition

Reduction to the allowance for certain loans acquired in transfer not accounted for as debt credit losses related to financing receivables deemed uncollectible.

+ References

No definition available.

+ Details

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- Definition

Allowance for loan and lease losses recoveries and write-off, net.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The provision for loan losses on acquired loans.

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No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Reserve for loans impairments recorded after acquisition as a result of current information and events which result in it being probable that estimated cash flows will be less than previously expected or because actual cash flows are less than cash flows previously expected. This relates to loans not accounted for as debt securities, with evidence of deterioration of credit quality since origination that was 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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=82894903&loc=d3e15032-111544

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 15
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82894507&loc=d3e13503-111538

+ Details

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