Securities Continuous Unrealized Loss (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	$ 13,335	$ 155,281
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Losses	56	8,034
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	66,870	16,273
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Losses	1,424	1,715
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	80,205	171,554
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Losses	1,480	9,749
US Government and Government Agencies and Authorities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	0	35,932
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Losses	0	3,181
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	24,126	8,590
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Losses	830	1,376
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	24,126	44,522
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Losses	830	4,557
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	9,078	109,774
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Losses	22	4,394
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	42,744	7,683
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Losses	594	339
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	51,822	117,457
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Losses	616	4,733
US States and Political Subdivisions Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	4,257	9,575
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Losses	34	459
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	0	0
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Losses	0	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	4,257	9,575
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Losses	$ 34	$ 459

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This item represents the aggregate fair value of investments in debt and equity securities in an unrealized loss position which are categorized neither as held-to-maturity nor trading securities.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

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This item represents the aggregate fair value of investments in debt and equity securities categorized neither as held-to-maturity nor trading securities that have been in a continuous unrealized loss position for less than twelve months.

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

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-Topic 320

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