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Securities (Securities Available for Sale) (Details) - USD ($) $ in Thousands | Sep. 30, 2015 | Dec. 31, 2014
--- | --- | ---
Schedule of Available-for-sale Securities [Line Items] |  |
Securities available-for-sale, amortized cost | $ 2,004,728 | $ 2,087,069
Available-for-sale Debt Securities Gross Unrealized Gain, instant | 29,138 | 25,527
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax | (6,442) | (14,339)
Securities available for sale | 2,027,424 | 2,098,257
U.S. Government Agency and Government-Sponsored Enterprise Mortgage-Backed Securities and Collateralized Mortgage Obligations [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Securities available-for-sale, amortized cost | 1,157,054 | 1,160,378
Available-for-sale Debt Securities Gross Unrealized Gain, instant | 12,610 | 10,219
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax | (5,132) | (8,210)
Securities available for sale | 1,164,532 | 1,162,387
State and Municipal Securities [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Securities available-for-sale, amortized cost | 476,650 | 483,578
Available-for-sale Debt Securities Gross Unrealized Gain, instant | 13,574 | 14,432
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax | (755) | (1,526)
Securities available for sale | 489,469 | 496,484
U.S. Government and Government-Sponsored Enterprise Securities [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Securities available-for-sale, amortized cost | 345,309 | 416,919
Available-for-sale Debt Securities Gross Unrealized Gain, instant | 2,922 | 856
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax | (375) | (4,069)
Securities available for sale | 347,856 | 413,706
US Government Securities [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Securities available-for-sale, amortized cost | 20,431 | 20,910
Available-for-sale Debt Securities Gross Unrealized Gain, instant | 1 | 0
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax | (32) | (411)
Securities available for sale | 20,400 | 20,499
Other Securities [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Securities available-for-sale, amortized cost | 5,284 | 5,284
Available-for-sale Debt Securities Gross Unrealized Gain, instant | 31 | 20
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax | (148) | (123)
Securities available for sale | $ 5,167 | $ 5,181

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- Definition Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=51813488&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (aa) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=49167202&loc=d3e26610-111562 + Details
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- Definition Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27161-111563 + Details
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