Federal Home Loan Bank Advances (Summary of Outstanding FHLB Advances) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Federal Home Loan Bank, Advances, Branch Of FHLB Bank [Line Items]
Federal Home Loan Bank advances	$ 153,831	$ 853,431
0.16% advance due January 2016
Federal Home Loan Bank, Advances, Branch Of FHLB Bank [Line Items]
Federal Home Loan Bank advances	$ 0	331,100
Debt instrument, interest rate, stated percentage	0.16%
Debt instrument, maturity date	2016
0.19% advance due January 2016
Federal Home Loan Bank, Advances, Branch Of FHLB Bank [Line Items]
Federal Home Loan Bank advances	$ 0	68,000
Debt instrument, interest rate, stated percentage	0.19%
Debt instrument, maturity date	2016
0.99% advance due February 2016
Federal Home Loan Bank, Advances, Branch Of FHLB Bank [Line Items]
Federal Home Loan Bank advances	$ 0	26,426
Debt instrument, interest rate, stated percentage	0.99%
Debt instrument, maturity date	2016
1.09% advance due February 2017
Federal Home Loan Bank, Advances, Branch Of FHLB Bank [Line Items]
Federal Home Loan Bank advances	$ 2,000	0
Debt instrument, interest rate, stated percentage	1.09%
Debt instrument, maturity date	2017
1.25% advance due February 2017
Federal Home Loan Bank, Advances, Branch Of FHLB Bank [Line Items]
Federal Home Loan Bank advances	$ 24,928	24,368
Debt instrument, interest rate, stated percentage	1.25%
Debt instrument, maturity date	2017
3.47% advance due November 2017
Federal Home Loan Bank, Advances, Branch Of FHLB Bank [Line Items]
Federal Home Loan Bank advances	$ 10,000	10,000
Debt instrument, interest rate, stated percentage	3.47%
Debt instrument, maturity date	2017
0.89% advance due December 2017
Federal Home Loan Bank, Advances, Branch Of FHLB Bank [Line Items]
Federal Home Loan Bank advances	$ 0	90,000
Debt instrument, interest rate, stated percentage	0.89%
Debt instrument, maturity date	2017
1.49% advance due February 2018
Federal Home Loan Bank, Advances, Branch Of FHLB Bank [Line Items]
Federal Home Loan Bank advances	$ 91,903	89,261
Debt instrument, interest rate, stated percentage	1.49%
Debt instrument, maturity date	2018
1.31% advance due August 2018
Federal Home Loan Bank, Advances, Branch Of FHLB Bank [Line Items]
Federal Home Loan Bank advances	$ 0	94,597
Debt instrument, interest rate, stated percentage	1.31%
Debt instrument, maturity date	2018
1.89% advance due August 2020
Federal Home Loan Bank, Advances, Branch Of FHLB Bank [Line Items]
Federal Home Loan Bank advances	$ 0	94,679
Debt instrument, interest rate, stated percentage	1.89%
Debt instrument, maturity date	2020
4.18% advance due February 2022
Federal Home Loan Bank, Advances, Branch Of FHLB Bank [Line Items]
Federal Home Loan Bank advances	$ 25,000	$ 25,000
Debt instrument, interest rate, stated percentage	4.18%
Debt instrument, maturity date	2022

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- Definition

The year of maturity, when only one maturity date applies, for the advances from the Federal Home Loan Bank 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 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

States the interest rate applicable to Federal Home Loan Bank advances outstanding 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

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- Definition

Including both current and noncurrent portions, Federal Home Loan Bank borrowings initially due beyond one year or beyond the normal operating cycle if longer.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=6479336&loc=d3e64702-112823

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