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Goodwill and Intangible Assets (Schedule of Goodwill and Intangible Assets) (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | ---
Sep. 30, 2015 | Sep. 30, 2014 | Sep. 30, 2015 | Sep. 30, 2014 | Jun. 30, 2015 | Dec. 31, 2014 | Jun. 30, 2014 | Dec. 31, 2013
Goodwill and Intangible Assets [Line Items] |  |  |  |  |  |  |  |
Goodwill, Purchase Accounting Adjustments | $ 225 | $ 0 | $ 225 | $ 0 |  |  |  |
Goodwill and Intangible Assets [Roll Forward] |  |  |  |  |  |  |  |
Total goodwill, beginning of period |  | 343,952 | 382,537 | 343,952 |  |  |  |
Total goodwill, end of period | 382,762 | 343,952 | 382,762 | 343,952 |  |  |  |
CDI current period amortization | (1,695) | (1,456) | (5,230) | (4,516) |  |  |  |
Indefinite-Lived Intangible Assets (Excluding Goodwill) | 919 | 919 | 919 | 919 |  |  |  |
Other intangible assets, net | 25,229 | 21,336 | 25,229 | 21,336 |  | $ 30,459 |  |
Total goodwill and intangible assets, end of period | 407,991 | 365,288 | $ 407,991 | 365,288 |  |  |  |
Core Deposits [Member] |  |  |  |  |  |  |  |
Goodwill and Intangible Assets [Line Items] |  |  |  |  |  |  |  |
Estimated life of CDI, in years |  |  | 10 years |  |  |  |  |
Goodwill and Intangible Assets [Roll Forward] |  |  |  |  |  |  |  |
Gross core deposit intangible balance, beginning of period |  |  |  |  | $ 58,598 | 58,598 | $ 47,698 | $ 47,698
Accumulated amortization at beginning of period |  |  |  |  | $ (32,593) | $ (29,058) | $ (25,825) | $ (22,765)
Core deposit intangible, net, beginning of period | 26,005 | 21,873 | $ 29,540 | 24,933 |  |  |  |
CDI current period amortization | (1,695) | (1,456) | (5,230) | (4,516) |  |  |  |
Total core deposit intangible, end of period | $ 24,310 | $ 20,417 | $ 24,310 | $ 20,417 |  |  |  |

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- Definition Goodwill and Intangible Assets [Roll Forward] + References No definition available. + Details
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- Definition Goodwill and intangible assets total + References No definition available. + Details
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- Definition The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16225-109274 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275 + Details
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- Definition Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275 + Details
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- Definition Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275 + Details
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- Definition Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 25 -Paragraph 16 -URI http://asc.fasb.org/extlink&oid=34752592&loc=d3e961-128460 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267 + Details
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- Definition Amount of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275 + Details
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- Definition Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16212-109274 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph ((a)(1),(b)) -URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275 + Details
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