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Securities (Securities Available for Sale) (Details) - USD ($) $ in Thousands | 3 Months Ended |
--- | --- | ---
Mar. 31, 2017 | Mar. 31, 2016 | Dec. 31, 2016
Schedule of Available-for-sale Securities [Line Items] |  |  |
Available-for-sale Securities, Gross Realized Gains (Losses), Sale Proceeds | $ 0 | $ 38,900 |
Securities available-for-sale, amortized cost | 2,349,149 |  | $ 2,299,037
Available-for-sale Debt Securities Gross Unrealized Gain, instant | 11,017 |  | 10,231
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax | (28,807) |  | (30,691)
Securities available for sale | 2,331,359 |  | 2,278,577
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 | 1,506,914 |  | 1,486,690
Available-for-sale Debt Securities Gross Unrealized Gain, instant | 2,400 |  | 2,760
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax | (22,816) |  | (23,718)
Securities available for sale | 1,486,498 |  | 1,465,732
State and Municipal Securities [Member] |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Securities available-for-sale, amortized cost | 484,376 |  | 473,914
Available-for-sale Debt Securities Gross Unrealized Gain, instant | 7,316 |  | 6,343
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax | (4,337) |  | (5,197)
Securities available for sale | 487,355 |  | 475,060
U.S. Government and Government-Sponsored Enterprise Securities [Member] |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Securities available-for-sale, amortized cost | 352,323 |  | 332,348
Available-for-sale Debt Securities Gross Unrealized Gain, instant | 1,241 |  | 1,065
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax | (1,381) |  | (1,511)
Securities available for sale | 352,183 |  | 331,902
US Government Securities [Member] |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Securities available-for-sale, amortized cost | 252 |  | 801
Available-for-sale Debt Securities Gross Unrealized Gain, instant | 0 |  | 0
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax | 0 |  | (1)
Securities available for sale | 252 |  | 800
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 | 60 |  | 63
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax | (273) |  | (264)
Securities available for sale | $ 5,071 |  | $ 5,083

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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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