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Deposits - Narrative (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Banking and Thrift [Abstract] |  |  |
Interest on time accounts | $ 576 | $ 743 | $ 853
Held-to-maturity securities pledged as collateral | 107,800 |  |
CDARS balance in reciprocal deposit program | 13,500 | 15,100 |
ICS balance in reciprocal deposit program | 41,000 | 29,000 |
DDM balance in reciprocal deposit program | 29,200 | 36,400 |
One-way CDARS deposits | 4,200 | 361 |
Deposit overdrafts reclassified as loan balances | 224 | 229 |
Related party deposit liabilities | $ 29,900 | $ 7,300 |

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- Definition Deposits, Demand Deposit Marketplace (DDM) + References No definition available. + Details
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- Definition Deposits, Money Market Deposits, Insured Cash Sweep (ICS) + References No definition available. + Details
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- Definition Certificate of Deposit Account Registry Service, a special type of certificate of deposit whereby the participating bank accepts deposits in excess of the FDIC insured maximum and places the deposits through a network to member banks in the CDARS(R) network in increments of less than the FDIC insured maximum to provide the depositor full FDIC insurance coverage. + References No definition available. + Details
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- Definition Time Deposits, Certificate Of Deposit Account Registry Service (CDARS), One-Way + References No definition available. + Details
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- References No definition available. + Details
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- Definition Amount of deposits held by the entity that have been reclassified as loan balances receivable, for example, but not limited to, overdrafts receivable. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 405 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=50488274&loc=d3e64164-112818 + Details
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- Definition The carrying amount of held-to-maturity securities that serve as collateral for borrowings. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5086-111524 + Details
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- Definition The aggregate interest expense incurred on time deposits, including certificates of deposits, in domestic offices. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.6) -URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882 + Details
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- Definition Amount of deposits held by the entity for a related party (entity, shareholder, employee). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(k)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 + Details
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