Subordinated Notes - Subordinated Notes, Including Debt Issuance Costs (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Subordinated debt	$ 98,482	$ 98,416
Subordinated notes – due 2027
Debt Instrument [Line Items]
Subordinated debt	$ 68,855	$ 68,829
Stated interest rate	4.25%	4.25%
Subordinated notes – due 2025
Debt Instrument [Line Items]
Subordinated debt	$ 29,627	$ 29,587
Stated interest rate	4.75%	4.75%
Subordinated Debt \| Subordinated notes – due 2027
Debt Instrument [Line Items]
Stated interest rate	4.25%
Subordinated Debt \| Subordinated notes – due 2025
Debt Instrument [Line Items]
Stated interest rate	4.75%
Subordinated Debt \| LIBOR \| Subordinated notes – due 2027
Debt Instrument [Line Items]
Basis spread on variable rate	2.05%
Subordinated Debt \| LIBOR \| Subordinated notes – due 2025
Debt Instrument [Line Items]
Basis spread on variable rate	3.068%

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

No definition available.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of subordinated debt (with initial maturities beyond one year or beyond the operating cycle if longer). Subordinated debt places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(19))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-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

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Details

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- Details

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