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Junior Subordinated Debentures - Junior Subordinated Debentures by Issuance (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016
Shares Subject To Mandatory Redemption By Settlement Terms [Line Items] |  |
Total liability, at par | $ 36,500 | $ 36,500
Total liability, at carrying value | 27,647 | 26,926
Metropolitan Statutory Trust 1 |  |
Shares Subject To Mandatory Redemption By Settlement Terms [Line Items] |  |
Total liability, at par | 35,000 | 35,000
RidgeStone Capital Trust I |  |
Shares Subject To Mandatory Redemption By Settlement Terms [Line Items] |  |
Total liability, at par | 1,500 | 1,500
Junior Subordinated Debentures |  |
Shares Subject To Mandatory Redemption By Settlement Terms [Line Items] |  |
Discount | $ (8,853) | $ (9,574)
Junior Subordinated Debentures | Metropolitan Statutory Trust 1 |  |
Shares Subject To Mandatory Redemption By Settlement Terms [Line Items] |  |
Stated Maturity | Mar. 17, 2034 |
Contractual Rate | 4.39% | 3.78%
Junior Subordinated Debentures | Metropolitan Statutory Trust 1 | Three-month LIBOR |  |
Shares Subject To Mandatory Redemption By Settlement Terms [Line Items] |  |
Interest Rate Spread, Description | Three-month LIBOR |
Interest rate spread | 2.79% | 2.79%
Junior Subordinated Debentures | RidgeStone Capital Trust I |  |
Shares Subject To Mandatory Redemption By Settlement Terms [Line Items] |  |
Stated Maturity | Jun. 30, 2033 |
Contractual Rate | 5.09% | 5.09%
Junior Subordinated Debentures | RidgeStone Capital Trust I | Five-year LIBOR |  |
Shares Subject To Mandatory Redemption By Settlement Terms [Line Items] |  |
Interest Rate Spread, Description | Five-year LIBOR |
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 The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR. + 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 Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format. + 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)(2)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Amount, after accumulated amortization, of debt discount. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 1A -URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28541-108399 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400 + Details
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- Definition Including the current and noncurrent portions, the carrying value of junior subordinated long-term debt owed to unconsolidated subsidiary trusts as of the balance sheet date. Such debt places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets and was initially scheduled to be repaid after one year or beyond the normal operating cycle if longer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.16) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.16) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
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