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Securities (Securities Available for Sale) (Details) - USD ($) $ in Thousands | Jun. 30, 2016 | Dec. 31, 2015
--- | --- | ---
Schedule of Available-for-sale Securities [Line Items] |  |
Securities available-for-sale, amortized cost | $ 2,237,264 | $ 2,157,610
Available-for-sale Debt Securities Gross Unrealized Gain, instant | 44,694 | 18,352
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax | (2,406) | (18,268)
Securities available for sale | 2,279,552 | 2,157,694
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 | 1,403,591 | 1,296,955
Available-for-sale Debt Securities Gross Unrealized Gain, instant | 20,196 | 4,525
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax | (2,101) | (14,991)
Securities available for sale | 1,421,686 | 1,286,489
State and Municipal Securities [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Securities available-for-sale, amortized cost | 500,618 | 480,417
Available-for-sale Debt Securities Gross Unrealized Gain, instant | 17,913 | 12,690
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax | (166) | (938)
Securities available for sale | 518,365 | 492,169
U.S. Government and Government-Sponsored Enterprise Securities [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Securities available-for-sale, amortized cost | 327,223 | 354,515
Available-for-sale Debt Securities Gross Unrealized Gain, instant | 6,520 | 1,113
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax | 0 | (1,846)
Securities available for sale | 333,743 | 353,782
US Government Securities [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Securities available-for-sale, amortized cost | 548 | 20,439
Available-for-sale Debt Securities Gross Unrealized Gain, instant | 1 | 0
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax | 0 | (302)
Securities available for sale | 549 | 20,137
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 | 64 | 24
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax | (139) | (191)
Securities available for sale | $ 5,209 | $ 5,117

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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=65884222&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=73527792&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=66010992&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=73527792&loc=d3e27161-111563 + Details
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- Definition Amount before tax of unrealized loss 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 (c) -URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27161-111563 + Details
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