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Fair Value Option and Fair Value Measurements - Nonrecurring (Details) (USD $) |  |  |  |  |  |  | 9 Months Ended | 12 Months Ended |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
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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 |  |  |  |  |  |  |  |  |  |  |  |

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- 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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- 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) -URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258 + Details
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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 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 28 -Article 12 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph c -Subparagraph Schedule III -Article 5 + Details
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