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Junior Subordinated Debentures - Additional Information (Details) - USD ($) | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016
Debt Instrument [Line Items] |  |
Principal amount | $ 36,500,000 | $ 36,500,000
Accrued interest payable | 1,306,000 | 2,427,000
Metropolitan Statutory Trust 1 |  |
Debt Instrument [Line Items] |  |
Principal amount | $ 35,000,000 | $ 35,000,000
Metropolitan Statutory Trust 1 | Junior Subordinated Debentures |  |
Debt Instrument [Line Items] |  |
Contractual rate | 4.39% | 3.78%
Accrued interest payable | $ 62,000 | $ 50,000
Metropolitan Statutory Trust 1 | Junior Subordinated Debentures | Three-month LIBOR |  |
Debt Instrument [Line Items] |  |
Interest rate spread | 2.79% | 2.79%
RidgeStone Capital Trust I |  |
Debt Instrument [Line Items] |  |
Principal amount | $ 1,500,000 | $ 1,500,000
RidgeStone Capital Trust I | Junior Subordinated Debentures |  |
Debt Instrument [Line Items] |  |
Contractual rate | 5.09% | 5.09%
Accrued interest payable | $ 0 | $ 0
RidgeStone Capital Trust I | Junior Subordinated Debentures | Five-year LIBOR |  |
Debt Instrument [Line Items] |  |
Interest rate spread | 3.50% | 3.50%

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- Definition Junior subordinated debenture owed to unconsolidated subsidiary trust, including unamortized discount. + References No definition available. + Details
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- Definition Percentage points added to the reference rate to compute the variable rate on the debt instrument. + References No definition available. + Details
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- Definition Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399 + Details
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- Definition Amount of interest payable on debt, including, but not limited to, trade payables. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.15(5)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.15(a)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 + Details
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- Details
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