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Reinsurance (Tables) | 12 Months Ended
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Dec. 31, 2017
Reinsurance Disclosures [Abstract] |
Schedule of Total Reinsurance Balances Segregated By Reinsurer |
|  | As of December 31, 2017 |  | As of December 31, 2016
($ in thousands) |  | Reinsurance Balances |  | % of Reinsurance Balance |  | Reinsurance Balances |  | % of Reinsurance Balance
Total reinsurance recoverables |  | $ | 594,832 |  |  |  |  |  | $ | 621,537 |  |  |  |
Total prepaid reinsurance premiums |  | 153,493 |  |  |  |  |  | 146,282 |  |  |  |
Total reinsurance balance |  | 748,325 |  |  |  |  |  | 767,819 |  |  |  |
Federal and state pools1: |  |  |  |  |  |  |  |  |  |  |  |
NFIP |  | 204,161 |  |  | 27 | % |  | 211,181 |  |  | 27 | %
New Jersey Unsatisfied Claim Judgment Fund |  | 62,947 |  |  | 9 |  |  | 65,574 |  |  | 9 |
Other |  | 3,634 |  |  | — |  |  | 3,227 |  |  | — |
Total federal and state pools |  | 270,742 |  |  | 36 |  |  | 279,982 |  |  | 36 |
Remaining reinsurance balance |  | $ | 477,583 |  |  | 64 |  |  | $ | 487,837 |  |  | 64 |
Munich Re Group (A.M. Best rated "A+") |  | $ | 117,460 |  |  | 16 |  |  | $ | 119,520 |  |  | 16 |
Hannover Ruckversicherungs AG (A.M. Best rated "A+") |  | 101,652 |  |  | 14 |  |  | 106,298 |  |  | 13 |
AXIS Reinsurance Company (A.M. Best rated "A+") |  | 62,396 |  |  | 8 |  |  | 59,737 |  |  | 8 |
Swiss Re Group (A.M. Best rated "A+") |  | 40,772 |  |  | 5 |  |  | 50,494 |  |  | 7 |
Partner Reinsurance Company of the U.S. (A.M. Best rated “A”) |  | 16,925 |  |  | 2 |  |  | 21,125 |  |  | 3 |
All other reinsurers |  | 138,378 |  |  | 19 |  |  | 130,663 |  |  | 17 |
Total reinsurers |  | 477,583 |  |  | 64 | % |  | 487,837 |  |  | 64 | %
Less: collateral2 |  | (122,413 | ) |  |  |  | (113,763 | ) |  |
Reinsurers, net of collateral |  | $ | 355,170 |  |  |  |  | $ | 374,074 |  |  |
1 Considered to have minimal risk of default. 2 Includes letters of credit, trust funds, and funds held against reinsurance recoverables.
List Of Direct, Assumed, And Ceded Reinsurance Amounts |
($ in thousands) |  | 2017 |  | 2016 |  | 2015
Premiums written: |  |  |  |  |  |  |  |  |
Direct |  | $ | 2,733,459 |  |  | 2,577,259 |  |  | 2,403,519 |
Assumed |  | 26,685 |  |  | 28,779 |  |  | 23,848 |
Ceded |  | (389,503 | ) |  | (368,750 | ) |  | (357,463 | )
Net |  | $ | 2,370,641 |  |  | 2,237,288 |  |  | 2,069,904 |
Premiums earned: |  |  |  |  |  |  |  |  |
Direct |  | $ | 2,647,488 |  |  | 2,484,715 |  |  | 2,330,267 |
Assumed |  | 25,831 |  |  | 28,214 |  |  | 23,209 |
Ceded |  | (382,292 | ) |  | (363,357 | ) |  | (363,567 | )
Net |  | $ | 2,291,027 |  |  | 2,149,572 |  |  | 1,989,909 |
Loss and loss expense incurred: |  |  |  |  |  |  |  |  |
Direct |  | $ | 1,570,678 |  |  | 1,560,356 |  |  | 1,274,872 |
Assumed |  | 17,588 |  |  | 22,708 |  |  | 16,996 |
Ceded |  | (243,192 | ) |  | (348,267 | ) |  | (143,327 | )
Net |  | $ | 1,345,074 |  |  | 1,234,797 |  |  | 1,148,541 |
Schedule of Ceded Premiums and Losses Related to Flood Operations |
Ceded to NFIP ($ in thousands) |  | 2017 |  | 2016 |  | 2015
Ceded premiums written |  | $ | (241,345 | ) |  | (232,245 | ) |  | (228,907 | )
Ceded premiums earned |  | (235,088 | ) |  | (227,882 | ) |  | (233,940 | )
Ceded loss and loss expense incurred |  | (160,922 | ) |  | (239,891 | ) |  | (62,078 | )

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