v2.4.0.8

Securities (Securities Available for Sale) (Details) (USD $) In Thousands, unless otherwise specified | 12 Months Ended
--- | ---
Dec. 31, 2013 | Dec. 31, 2012 | Dec. 31, 2011
Schedule of Available-for-sale Securities [Line Items] |  |  |
Amortized Cost | $ 1,680,491 | $ 969,359 |
Gross Unrealized Gains | 22,551 | 38,606 |
Gross Unrealized Losses | 38,931 | 6,300 |
Fair Value | 1,664,111 | 1,001,665 |
Available-for-sale Securities, Gross Realized Gain (Loss) [Abstract] |  |  |
Gross realized losses | 170 | 714 | 250
Gross realized gains | 632 | 4,400 | 384
U.S. Government Agency and Government-Sponsored Enterprise Mortgage-Backed Securities and Collateralized Mortgage Obligations [Member] |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Amortized Cost | 961,442 | 561,076 |
Gross Unrealized Gains | 10,640 | 16,719 |
Gross Unrealized Losses | 23,674 | 5,426 |
Fair Value | 948,408 | 572,369 |
State and Municipal Securities [Member] |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Amortized Cost | 357,013 | 265,070 |
Gross Unrealized Gains | 11,450 | 20,893 |
Gross Unrealized Losses | 3,993 | 388 |
Fair Value | 364,470 | 285,575 |
U.S. Government Agency and Government-Sponsored Enterprise Securities [Member] |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Amortized Cost | 335,671 | 120,085 |
Gross Unrealized Gains | 434 | 851 |
Gross Unrealized Losses | 10,066 | 435 |
Fair Value | 326,039 | 120,501 |
US Treasury Securities [Member] |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Amortized Cost | 21,081 | 19,804 |
Gross Unrealized Gains | 0 | 39 |
Gross Unrealized Losses | 967 | 15 |
Fair Value | 20,114 | 19,828 |
Other Securities [Member] |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Amortized Cost | 5,284 | 3,324 |
Gross Unrealized Gains | 27 | 104 |
Gross Unrealized Losses | 231 | 36 |
Fair Value | $ 5,080 | $ 3,392 |

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