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Reinsurance (List of Direct, Assumed, and Ceded Reinsurance Amounts) (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2016 | Jun. 30, 2015 | Jun. 30, 2016 | Jun. 30, 2015
Premiums written: |  |  |  |
Direct | $ 665,862 | $ 621,408 | $ 1,312,140 | $ 1,220,191
Assumed | 7,788 | 4,960 | 14,108 | 11,041
Ceded | (95,510) | (94,235) | (182,749) | (181,011)
Net | 578,140 | 532,133 | 1,143,499 | 1,050,221
Premiums earned: |  |  |  |
Direct | 612,406 | 576,107 | 1,219,067 | 1,138,149
Assumed | 7,171 | 5,093 | 13,441 | 11,001
Ceded | (87,645) | (90,891) | (178,118) | (182,718)
Net | 531,932 | 490,309 | 1,054,390 | 966,432
Loss and loss expense incurred: |  |  |  |
Direct | 362,064 | 316,648 | 723,703 | 628,894
Assumed | 6,140 | 4,228 | 12,495 | 8,890
Ceded | (69,725) | (29,315) | (140,575) | (61,224)
Net | 298,479 | 291,561 | 595,623 | 576,560
National Flood Insurance Program [Member] |  |  |  |
Premiums written: |  |  |  |
Ceded | (63,906) | (62,479) | (117,154) | (116,321)
Premiums earned: |  |  |  |
Ceded | (56,667) | (58,781) | (113,481) | (117,779)
Loss and loss expense incurred: |  |  |  |
Ceded | $ (24,261) | $ (14,684) | $ (64,979) | $ (20,933)

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