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Securities - Unrealized Loss Positions (Details) (USD $) In Thousands, unless otherwise specified | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2014 security | Dec. 31, 2013 security
Number of Securities |  |
Less than 12 months in an unrealized loss position | 33 | 27
Greater than 12 months in an unrealized loss position | 11 | 5
Total | 44 | 32
Unrealized Losses |  |
Less than 12 months in an unrealized loss position | $ 2,932 | $ 6,633
Greater than 12 months in an unrealized loss position | 2,739 | 532
Total | 5,671 | 7,165
Fair Value |  |
Less than 12 months in an unrealized loss position | 241,940 | 170,149
Greater than 12 months in an unrealized loss position | 71,657 | 10,836
Total | 313,597 | 180,985
Number of Securities |  |
Less than 12 months in an unrealized loss position | 14 | 25
Greater than 12 months in an unrealized loss position | 2 |
Total | 16 | 25
Unrealized Losses |  |
Less than 12 months in an unrealized loss position | 1,175 | 2,931
Greater than 12 months in an unrealized loss position | 885 |
Total | 2,060 | 2,931
Fair Value |  |
Less than 12 months in an unrealized loss position | 85,517 | 175,766
Greater than 12 months in an unrealized loss position | 37,828 |
Total | 123,345 | 175,766
U.S. Treasury |  |
Number of Securities |  |
Less than 12 months in an unrealized loss position | 1 | 1
Total | 1 | 1
Unrealized Losses |  |
Less than 12 months in an unrealized loss position | 1 | 5
Total | 1 | 5
Fair Value |  |
Less than 12 months in an unrealized loss position | 1,532 | 1,544
Total | 1,532 | 1,544
U.S. government agencies |  |
Number of Securities |  |
Greater than 12 months in an unrealized loss position | 1 | 1
Total | 1 | 1
Unrealized Losses |  |
Greater than 12 months in an unrealized loss position | 80 | 66
Total | 80 | 66
Fair Value |  |
Greater than 12 months in an unrealized loss position | 1,638 | 1,672
Total | 1,638 | 1,672
U.S. government agency mortgage-backed |  |
Number of Securities |  |
Less than 12 months in an unrealized loss position | 1 |
Total | 1 |
Unrealized Losses |  |
Less than 12 months in an unrealized loss position | 11 |
Total | 11 |
Fair Value |  |
Less than 12 months in an unrealized loss position | 1,972 |
Total | 1,972 |
Number of Securities |  |
Less than 12 months in an unrealized loss position |  | 6
Total |  | 6
Unrealized Losses |  |
Less than 12 months in an unrealized loss position |  | 73
Total |  | 73
Fair Value |  |
Less than 12 months in an unrealized loss position |  | 19,134
Total |  | 19,134
States and political subdivisions |  |
Number of Securities |  |
Less than 12 months in an unrealized loss position | 3 | 6
Greater than 12 months in an unrealized loss position | 2 |
Total | 5 | 6
Unrealized Losses |  |
Less than 12 months in an unrealized loss position | 215 | 217
Greater than 12 months in an unrealized loss position | 13 |
Total | 228 | 217
Fair Value |  |
Less than 12 months in an unrealized loss position | 4,450 | 4,625
Greater than 12 months in an unrealized loss position | 1,862 |
Total | 6,312 | 4,625
Corporate bonds |  |
Number of Securities |  |
Less than 12 months in an unrealized loss position | 5 | 4
Greater than 12 months in an unrealized loss position | 2 | 2
Total | 7 | 6
Unrealized Losses |  |
Less than 12 months in an unrealized loss position | 463 | 429
Greater than 12 months in an unrealized loss position | 93 | 219
Total | 556 | 648
Fair Value |  |
Less than 12 months in an unrealized loss position | 20,581 | 10,493
Greater than 12 months in an unrealized loss position | 2,411 | 2,796
Total | 22,992 | 13,289
Collateralized mortgage obligations |  |
Number of Securities |  |
Less than 12 months in an unrealized loss position | 1 | 5
Greater than 12 months in an unrealized loss position | 3 |
Total | 4 | 5
Unrealized Losses |  |
Less than 12 months in an unrealized loss position | 18 | 3,146
Greater than 12 months in an unrealized loss position | 1,557 |
Total | 1,575 | 3,146
Fair Value |  |
Less than 12 months in an unrealized loss position | 4,739 | 54,021
Greater than 12 months in an unrealized loss position | 21,704 |
Total | 26,443 | 54,021
Number of Securities |  |
Less than 12 months in an unrealized loss position | 13 | 19
Greater than 12 months in an unrealized loss position | 2 |
Total | 15 | 19
Unrealized Losses |  |
Less than 12 months in an unrealized loss position | 1,164 | 2,858
Greater than 12 months in an unrealized loss position | 885 |
Total | 2,049 | 2,858
Fair Value |  |
Less than 12 months in an unrealized loss position | 83,545 | 156,632
Greater than 12 months in an unrealized loss position | 37,828 |
Total | 121,373 | 156,632
Asset-backed securities |  |
Number of Securities |  |
Less than 12 months in an unrealized loss position | 10 | 11
Greater than 12 months in an unrealized loss position | 3 | 2
Total | 13 | 13
Unrealized Losses |  |
Less than 12 months in an unrealized loss position | 1,231 | 2,836
Greater than 12 months in an unrealized loss position | 996 | 247
Total | 2,227 | 3,083
Fair Value |  |
Less than 12 months in an unrealized loss position | 117,440 | 99,466
Greater than 12 months in an unrealized loss position | 44,042 | 6,368
Total | 161,482 | 105,834
Collateralized loan obligations |  |
Number of Securities |  |
Less than 12 months in an unrealized loss position | 13 |
Total | 13 |
Unrealized Losses |  |
Less than 12 months in an unrealized loss position | 1,004 |
Total | 1,004 |
Fair Value |  |
Less than 12 months in an unrealized loss position | 93,198 |
Total | $ 93,198 |

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