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Reinsurance (List of Direct, Assumed, and Ceded Reinsurance Amounts) (Details) (USD $) In Thousands, unless otherwise specified | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2014 | Jun. 30, 2013 | Jun. 30, 2014 | Jun. 30, 2013
Premiums written: |  |  |  |
Direct | $ 572,314 | $ 551,190 | $ 1,130,205 | $ 1,080,006
Assumed | 5,837 | 4,378 | 13,687 | 12,860
Ceded premiums written | (98,328) | (93,391) | (187,319) | (180,565)
Net | 479,823 | 462,177 | 956,573 | 912,301
Premiums earned: |  |  |  |
Direct | 544,913 | 504,081 | 1,081,613 | 998,147
Assumed | 10,385 | 8,951 | 20,570 | 21,414
Ceded premiums earned | (91,673) | (86,780) | (182,063) | (172,369)
Net | 463,625 | 426,252 | 920,120 | 847,192
Loss and loss expense incurred: |  |  |  |
Direct | 332,707 | 338,954 | 691,056 | 704,600
Assumed | 7,377 | 6,420 | 14,856 | 15,494
Ceded loss and loss expense incurred | (42,289) | (65,780) | (87,571) | (170,651)
Net | $ 297,795 | $ 279,594 | $ 618,341 | $ 549,443
Number of insurance subsidiaries |  |  | 10 |
Percentage of NFIP claims ceded by federal government |  |  | 100.00% |

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