FHLB Advances (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Interest Expense, Federal Home Loan Bank and Federal Reserve Bank Advances, Short-term	$ 541
Investment in FHLB stock	11,475	$ 0
Federal Home Loan Bank of Indianapolis [Member]
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Federal Home Loan Bank, Advances, General Debt Obligations, Disclosures, Collateral Pledged	541,771
FHLB advances	520,000
Investment in FHLB stock	$ 11,475
Federal Home Loan Bank, Advances, Branch of FHLB Bank, Weighted Average Interest Rate	0.40%
RMBS [Member] \| Federal Home Loan Bank of Indianapolis [Member]
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
FHLB advances	$ 17,000
CMBS [Member] \| Federal Home Loan Bank of Indianapolis [Member]
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
FHLB advances	503,000
30 to 90 days [Member] \| Federal Home Loan Bank of Indianapolis [Member]
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
FHLB advances	$ 257,000
Federal Home Loan Bank, Advances, Branch of FHLB Bank, Weighted Average Interest Rate	0.28%
30 to 90 days [Member] \| RMBS [Member] \| Federal Home Loan Bank of Indianapolis [Member]
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
FHLB advances	$ 17,000
30 to 90 days [Member] \| CMBS [Member] \| Federal Home Loan Bank of Indianapolis [Member]
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
FHLB advances	240,000
Maturity Greater than 90 Days [Member] \| Federal Home Loan Bank of Indianapolis [Member]
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
FHLB advances	$ 263,000
Federal Home Loan Bank, Advances, Branch of FHLB Bank, Weighted Average Interest Rate	0.51%
Maturity Greater than 90 Days [Member] \| RMBS [Member] \| Federal Home Loan Bank of Indianapolis [Member]
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
FHLB advances	$ 0
Maturity Greater than 90 Days [Member] \| CMBS [Member] \| Federal Home Loan Bank of Indianapolis [Member]
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
FHLB advances	$ 263,000

Amount of advances from the Federal Home Loan Bank (FHLB).

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- Definition

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+ References

No definition available.

+ Details

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- Definition

Describes the weighted average interest rate applicable to the specific advances from the Federal Home Loan Bank, by branch, as of the Balance Sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6479336&loc=d3e64711-112823

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Amount of the collateral pledged in support of federal home loan bank advances outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=6479336&loc=d3e64711-112823

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- Definition

Federal Home Loan Bank (FHLB) stock represents an equity interest in a FHLB. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 325
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6478792&loc=d3e63345-112809

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- Definition

Interest expense incurred during the reporting period on short-term borrowings associated with Federal Home Loan Bank and Federal Reserve Bank advances.

+ References

No definition available.

+ Details

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