v2.4.0.8

Investments - Fair Value and Unrealized Losses (Details) (USD $) In Thousands, unless otherwise specified | Mar. 31, 2014 securities | Dec. 31, 2013 securities
--- | --- | ---
Fair value |  |
12 Months or More, Fair value |  | $ 229,896
Total, Fair value |  | 1,582,739
Unrealized losses |  |
12 Months or More, Unrealized losses |  | (8,826)
Total, Unrealized losses |  | (66,373)
Number of securities in loss position (in securities) | 103 | 140
12 Months or More, number of securities (in securities) | 24 | 19
U.S. agency bonds – mortgage-backed [Member] |  |
Fair value |  |
Less than 12 Months, Fair value | 743,882 | 795,439
12 Months or More, Fair value | 109,169 | 60,602
Total, Fair value | 853,051 | 856,041
Unrealized losses |  |
Less than 12 Months, Unrealized losses | (30,320) | (38,421)
12 Months or More, Unrealized losses | (3,887) | (2,683)
Total, Unrealized losses | (34,207) | (41,104)
Non-U.S. government bonds [Member] |  |
Fair value |  |
Less than 12 Months, Fair value | 7,968 | 9,946
12 Months or More, Fair value | 0 | 0
Total, Fair value | 7,968 | 9,946
Unrealized losses |  |
Less than 12 Months, Unrealized losses | (331) | (712)
12 Months or More, Unrealized losses | 0 | 0
Total, Unrealized losses | (331) | (712)
Other mortgage-backed bonds [Member] |  |
Fair value |  |
Less than 12 Months, Fair value |  | 33,444
12 Months or More, Fair value |  | 0
Total, Fair value |  | 33,444
Unrealized losses |  |
Less than 12 Months, Unrealized losses |  | (232)
12 Months or More, Unrealized losses |  | 0
Total, Unrealized losses |  | (232)
Corporate bonds [Member] |  |
Fair value |  |
Less than 12 Months, Fair value | 183,710 | 463,469
12 Months or More, Fair value | 168,371 | 169,294
Total, Fair value | 352,081 | 632,763
Unrealized losses |  |
Less than 12 Months, Unrealized losses | (6,590) | (16,687)
12 Months or More, Unrealized losses | (5,062) | (6,143)
Total, Unrealized losses | (11,652) | (22,830)
Municipal bonds – other [Member] |  |
Fair value |  |
Less than 12 Months, Fair value |  | 50,545
12 Months or More, Fair value |  | 0
Total, Fair value |  | 50,545
Unrealized losses |  |
Less than 12 Months, Unrealized losses |  | (1,495)
12 Months or More, Unrealized losses |  | 0
Total, Unrealized losses |  | (1,495)
Available-for-sale securities [Member] |  |
Fair value |  |
Less than 12 Months, Fair value | 935,560 | 1,352,843
12 Months or More, Fair value | 277,540 | 229,896
Total, Fair value | 1,213,100 | 1,582,739
Unrealized losses |  |
Less than 12 Months, Unrealized losses | (37,241) | (57,547)
12 Months or More, Unrealized losses | (8,949) | (8,826)
Total, Unrealized losses | $ (46,190) | $ (66,373)

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