Derivative Instruments (Details) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2017 USD ($) instrument	Jun. 30, 2016 USD ($)	Jun. 30, 2017 USD ($) instrument	Jun. 30, 2016 USD ($)	Dec. 31, 2016 USD ($) instrument
Notional Amount	$ 645,039		$ 645,039		$ 605,580
Asset Derivatives Fair Value	4,187		4,187		5,785
Liabilities Derivatives Fair Value	(931)		(931)		$ (643)
Net Realized Gain (Loss)	(118)	$ (564)	(343)	$ (1,129)
Net Change in Unrealized Gain (Loss)	$ (476)	(761)	$ (1,886)	(3,037)
Credit default swaps
Number of derivative instrument held \| instrument	1		1		1
Credit default swaps \| Credit Risk
Notional Amount	$ 15,000		$ 15,000		$ 15,000
Asset Derivatives Fair Value	95		95		$ 173
Credit default swaps \| Net Unrealized Gain (Loss) on Financial Instruments
Net Change in Unrealized Gain (Loss)	$ (108)	(116)	$ (78)	(165)
Interest rate swaps
Number of derivative instrument held \| instrument	49		49		49
Liabilities Derivatives Fair Value	$ (931)		$ (931)		$ (643)
Interest rate swaps \| Interest Rate Risk
Notional Amount	412,550		412,550		378,050
Asset Derivatives Fair Value	1,373		1,373		2,922
Liabilities Derivatives Fair Value	(931)		(931)		(643)
Interest rate swaps \| Net Realized Gain (Loss) on Financial Instruments
Net Realized Gain (Loss)	(118)	(564)	(343)	(1,129)
Interest rate swaps \| Net Unrealized Gain (Loss) on Financial Instruments
Net Change in Unrealized Gain (Loss)	(103)	$ (645)	32	$ (2,872)
Residential mortgage banking activities interest rate swaps \| Residential Mortgage Banking Activities
Net Change in Unrealized Gain (Loss)	(1,606)		(1,869)
Interest rate lock commitments (IRLCs) \| Interest Rate Risk
Notional Amount	217,489		217,489		212,530
Asset Derivatives Fair Value	2,719		2,719		$ 2,690
Interest rate lock commitments (IRLCs) \| Residential Mortgage Banking Activities
Net Change in Unrealized Gain (Loss)	$ 1,341		$ 29

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

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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+ References

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-Name Accounting Standards Codification
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-SubTopic 20
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-Paragraph 4D
-Subparagraph (c)(2)
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Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

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The number of derivative instruments of a particular group held by the entity.

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Amount of unrealized gain (loss) recognized in the income statement for a financial instrument classified as derivative asset (liability) after deduction of derivative liability (asset), measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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