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Reinsurance (List of Direct, Assumed, and Ceded Reinsurance Amounts) (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2016 | Sep. 30, 2015 | Sep. 30, 2016 | Sep. 30, 2015
Premiums written: |  |  |  |
Direct | $ 669,844 | $ 631,429 | $ 1,981,984 | $ 1,851,620
Assumed | 7,644 | 6,099 | 21,752 | 17,140
Ceded | (98,715) | (92,503) | (281,464) | (273,514)
Net | 578,773 | 545,025 | 1,722,272 | 1,595,246
Premiums earned: |  |  |  |
Direct | 627,520 | 590,716 | 1,846,587 | 1,728,865
Assumed | 7,163 | 5,830 | 20,604 | 16,831
Ceded | (92,254) | (89,156) | (270,372) | (271,874)
Net | 542,429 | 507,390 | 1,596,819 | 1,473,822
Loss and loss expense incurred: |  |  |  |
Direct | 428,520 | 306,635 | 1,152,223 | 935,529
Assumed | 5,929 | 4,224 | 18,424 | 13,114
Ceded | (118,191) | (25,698) | (258,766) | (86,922)
Net | 316,258 | 285,161 | 911,881 | 861,721
National Flood Insurance Program [Member] |  |  |  |
Premiums written: |  |  |  |
Ceded | (62,051) | (62,463) | (179,205) | (178,784)
Premiums earned: |  |  |  |
Ceded | (56,505) | (58,340) | (169,986) | (176,119)
Loss and loss expense incurred: |  |  |  |
Ceded | $ (99,200) | $ (15,382) | $ (164,179) | $ (36,315)

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