v2.4.0.8

Investments - Fair Value and Unrealized Losses (Details) (USD $) In Thousands, unless otherwise specified | Jun. 30, 2013 securities | Dec. 31, 2012 securities
--- | --- | ---
Fair value |  |
Less than 12 months, Fair Value | $ 1,011,713 | $ 253,333
12 Months or More, Fair value | 135,523 | 143,853
Total, Fair value | 1,147,236 | 397,186
Unrealized losses |  |
Less than 12 months, Unrealized losses | (41,631) | (2,571)
12 Months or More, Unrealized losses | (3,455) | (5,445)
Total, Unrealized losses | (45,086) | (8,016)
Number of securities in loss position (in securities) | 118 | 32
12 Months or More, number of securities (in securities) | 9 | 9
U.S. agency bonds – mortgage-backed [Member] |  |
Fair value |  |
Less than 12 Months, Fair value | 627,532 | 158,591
12 Months or More, Fair value | 9,104 | 0
Total, Fair value | 636,636 | 158,591
Unrealized losses |  |
Less than 12 Months, Unrealized losses | (19,210) | (1,473)
12 Months or More, Unrealized losses | (246) | 0
Total, Unrealized losses | (19,456) | (1,473)
Non-U.S. government bonds [Member] |  |
Fair value |  |
Less than 12 Months, Fair value | 27,630 |
12 Months or More, Fair value | 0 |
Total, Fair value | 27,630 |
Unrealized losses |  |
Less than 12 Months, Unrealized losses | (918) |
12 Months or More, Unrealized losses | 0 |
Total, Unrealized losses | (918) |
Corporate bonds [Member] |  |
Fair value |  |
Less than 12 Months, Fair value | 343,524 | 94,742
12 Months or More, Fair value | 123,920 | 141,842
Total, Fair value | 467,444 | 236,584
Unrealized losses |  |
Less than 12 Months, Unrealized losses | (21,309) | (1,098)
12 Months or More, Unrealized losses | (3,196) | (5,394)
Total, Unrealized losses | (24,505) | (6,492)
Other mortgage-backed bonds [Member] |  |
Fair value |  |
Less than 12 Months, Fair value | 13,027 |
12 Months or More, Fair value | 0 |
Total, Fair value | 13,027 |
Unrealized losses |  |
Less than 12 Months, Unrealized losses | (194) |
12 Months or More, Unrealized losses | 0 |
Total, Unrealized losses | (194) |
Available-for-sale securities [Member] |  |
Fair value |  |
Less than 12 Months, Fair value | 1,011,713 | 253,333
12 Months or More, Fair value | 133,024 | 141,842
Total, Fair value | 1,144,737 | 395,175
Unrealized losses |  |
Less than 12 Months, Unrealized losses | (41,631) | (2,571)
12 Months or More, Unrealized losses | (3,442) | (5,394)
Total, Unrealized losses | (45,073) | (7,965)
Other investments [Member] |  |
Fair value |  |
Less than 12 months, Fair Value | 0 | 0
12 Months or More, Fair value | 2,499 | 2,011
Total, Fair value | 2,499 | 2,011
Unrealized losses |  |
Less than 12 months, Unrealized losses | 0 | 0
12 Months or More, Unrealized losses | (13) | (51)
Total, Unrealized losses | $ (13) | $ (51)

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