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Fair Value Option and Fair Value Measurements - Nonrecurring (Details) (USD $)							9 Months Ended	12 Months Ended
	Sep. 30, 2014	Jun. 30, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Dec. 31, 2012	Sep. 30, 2014 Nonrecurring Impaired loans	Dec. 31, 2013 Nonrecurring Impaired loans	Sep. 30, 2014 Nonrecurring Impaired loans Carrying Amount	Dec. 31, 2013 Nonrecurring Impaired loans Carrying Amount	Sep. 30, 2014 Nonrecurring Other real estate owned	Dec. 31, 2013 Nonrecurring Other real estate owned	Sep. 30, 2014 Nonrecurring Level 3	Dec. 31, 2013 Nonrecurring Level 3	Sep. 30, 2014 Nonrecurring Level 3 Impaired loans	Dec. 31, 2013 Nonrecurring Level 3 Impaired loans	Sep. 30, 2014 Nonrecurring Level 3 Other real estate owned	Dec. 31, 2013 Nonrecurring Level 3 Other real estate owned	Sep. 30, 2014 Nonrecurring Total	Dec. 31, 2013 Nonrecurring Total	Sep. 30, 2014 Nonrecurring Total Impaired loans	Dec. 31, 2013 Nonrecurring Total Impaired loans	Sep. 30, 2014 Nonrecurring Total Other real estate owned	Dec. 31, 2013 Nonrecurring Total Other real estate owned
Assets and liabilities measured at fair value
Total									$ 1,500,000	$ 11,500,000			$ 41,834,000	$ 50,640,000	$ 957,000	$ 9,103,000	$ 40,877,000	$ 41,537,000	$ 41,834,000	$ 50,640,000	$ 957,000	$ 9,103,000	$ 40,877,000	$ 41,537,000
Valuation allowance	541,000		2,395,000				541,000	2,400,000
Decrease of specific allocations within the provision for loan losses							1,900,000	3,900,000
Carrying value of other real estate owned	40,877,000	39,232,000	41,537,000	49,066,000	59,465,000	72,423,000					40,900,000	41,500,000
Outstanding balance											61,700,000	65,900,000
OREO Valuation allowance	19,045,000	17,873,000	22,284,000	24,587,000	30,487,000	31,454,000					19,000,000	22,300,000
OREO participations											$ 1,800,000	$ 2,100,000

X

- Definition

Represents the amount of increase (decrease) in specific allocations within the provision for loan losses for impaired financing receivables.

+ References

No definition available.

+ Details

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X

- Definition

Represents the gross carrying amount of real estate owned before the valuation allowance.

+ References

No definition available.

+ Details

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X

- Definition

Represents the amount of the participations in the real estate owned.

+ References

No definition available.

+ Details

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X

- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)

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- Definition

Amount of allowance for credit losses related to recorded investment.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (a)(3)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=d3e5212-111524

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- Definition

Carrying amount as of the balance sheet date of land and buildings obtained through foreclosure proceedings or defeasance in full or partial satisfaction of a debt arrangement.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 45

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=28367877&loc=d3e4437-111522



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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 28

-Article 12



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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

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-Paragraph c

-Subparagraph Schedule III

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For each period for which an income statement is required, disclosure of the changes in the allowance, including balances at end of period.

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-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 210

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-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878



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