Off Balance sheets Activities and Derivatives - Mortgage Banking (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2016	Dec. 31, 2015
Fair values of derivative instruments in the balance sheet
Loans held for sale	$ 23,499	$ 18,952
Closed hedge instruments not settled	2,800	4,800
Forward loan sale commitments
Fair values of derivative instruments in the balance sheet
Forward commitments	47,800	31,300
To Be Announced securities
Fair values of derivative instruments in the balance sheet
Forward commitments	18,500	4,000
Mandatory Delivery Contracts
Fair values of derivative instruments in the balance sheet
Forward commitments	2,500	2,800
Best Efforts Contracts
Fair values of derivative instruments in the balance sheet
Forward commitments	26,800	24,500
Interest rate lock commitments
Fair values of derivative instruments in the balance sheet
Commitments to borrowers	29,900	13,100
Not Designated As Hedging Instruments
Fair values of derivative instruments in the balance sheet
Assets, Fair Value	1,002	220
Liabilities, Fair Value	793	180
Not Designated As Hedging Instruments \| Derivative loan commitments
Fair values of derivative instruments in the balance sheet
Assets, Fair Value	1,002	217
Not Designated As Hedging Instruments \| Commitments hedged with best efforts \| Other assets
Fair values of derivative instruments in the balance sheet
Assets, Fair Value	612	162
Not Designated As Hedging Instruments \| Commitments hedged with TBA \| Other assets
Fair values of derivative instruments in the balance sheet
Assets, Fair Value	390	55
Not Designated As Hedging Instruments \| Forward loan sale commitments
Fair values of derivative instruments in the balance sheet
Assets, Fair Value		3
Liabilities, Fair Value	793	180
Not Designated As Hedging Instruments \| To Be Announced securities \| Other liabilities.
Fair values of derivative instruments in the balance sheet
Liabilities, Fair Value	226	5
Not Designated As Hedging Instruments \| Mandatory Delivery Contracts \| Other assets
Fair values of derivative instruments in the balance sheet
Assets, Fair Value		3
Not Designated As Hedging Instruments \| Mandatory Delivery Contracts \| Other liabilities.
Fair values of derivative instruments in the balance sheet
Liabilities, Fair Value	13
Not Designated As Hedging Instruments \| Best Efforts Contracts \| Other liabilities.
Fair values of derivative instruments in the balance sheet
Liabilities, Fair Value	$ 554	$ 175

Amount of closed hedge instruments that are not settled.

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- Definition

This element represents the notional amount of a forward commitment to sell a loan agreement.

+ References

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- Definition

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)
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-Publisher FASB
-Name Accounting Standards Codification
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Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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.

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- Definition

Amount, after allowance for bad debt, of loan receivables held-for-sale that are not part of a disposal group. Excludes loans and leases covered under loss sharing agreements and loans classified as debt securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 45
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-URI http://asc.fasb.org/extlink&oid=28367877&loc=d3e4428-111522

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