v3.8.0.1

Investments - Fair Value and Unrealized Losses (Details) $ in Thousands | Sep. 30, 2017 USD ($) security | Dec. 31, 2016 USD ($) security
--- | --- | ---
Fixed maturities, Fair value |  |
Less than 12 Months, Fair value | $ 887,309 | $ 1,674,889
12 Months or More, Fair value | 672,040 | 431,159
Total, Fair value | 1,559,349 | 2,106,048
Fixed maturities, Unrealized losses |  |
Less than 12 months, Unrealized losses | (11,203) | (29,738)
12 months or more, Unrealized losses | (21,804) | (57,444)
Total, Unrealized losses | $ (33,007) | $ (87,182)
Number of securities in an unrealized loss position | security | 148 | 251
Investments fair value | $ 1,559,349 | $ 2,106,048
Investments, unrealized losses | $ 33,007 | $ 87,182
Number of securities in an unrealized loss position for 12 months or greater | security | 93 | 91
Investments fair value, unrealized loss position for 12 months or greater | $ 672,040 | $ 431,159
Investments in unrealized loss position for 12 months or greater, unrealized losses | 21,804 | 57,444
U.S. treasury bonds [Member] |  |
Fixed maturities, Fair value |  |
Less than 12 Months, Fair value | 0 | 589
12 Months or More, Fair value | 592 | 0
Total, Fair value | 592 | 589
Fixed maturities, Unrealized losses |  |
Less than 12 months, Unrealized losses | 0 | (11)
12 months or more, Unrealized losses | (8) | 0
Total, Unrealized losses | (8) | (11)
U.S. agency bonds – mortgage-backed [Member] |  |
Fixed maturities, Fair value |  |
Less than 12 Months, Fair value | 700,173 | 997,943
12 Months or More, Fair value | 390,211 | 47,969
Total, Fair value | 1,090,384 | 1,045,912
Fixed maturities, Unrealized losses |  |
Less than 12 months, Unrealized losses | (5,545) | (14,440)
12 months or more, Unrealized losses | (6,906) | (2,825)
Total, Unrealized losses | (12,451) | (17,265)
Non-U.S. government and supranational bonds [Member] |  |
Fixed maturities, Fair value |  |
Less than 12 Months, Fair value | 12,678 | 3,169
12 Months or More, Fair value | 15,132 | 25,236
Total, Fair value | 27,810 | 28,405
Fixed maturities, Unrealized losses |  |
Less than 12 months, Unrealized losses | (1,116) | (160)
12 months or more, Unrealized losses | (896) | (5,137)
Total, Unrealized losses | (2,012) | (5,297)
Asset-backed securities [Member] |  |
Fixed maturities, Fair value |  |
Less than 12 Months, Fair value | 21,499 | 30,589
12 Months or More, Fair value | 3,323 | 0
Total, Fair value | 24,822 | 30,589
Fixed maturities, Unrealized losses |  |
Less than 12 months, Unrealized losses | (105) | (69)
12 months or more, Unrealized losses | (59) | 0
Total, Unrealized losses | (164) | (69)
Corporate bonds [Member] |  |
Fixed maturities, Fair value |  |
Less than 12 Months, Fair value | 152,959 | 642,599
12 Months or More, Fair value | 262,782 | 357,954
Total, Fair value | 415,741 | 1,000,553
Fixed maturities, Unrealized losses |  |
Less than 12 months, Unrealized losses | (4,437) | (15,058)
12 months or more, Unrealized losses | (13,935) | (49,482)
Total, Unrealized losses | $ (18,372) | $ (64,540)

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