v2.4.0.8

Segments - Net Premiums (Details) (USD $) In Thousands, unless otherwise specified | 3 Months Ended
--- | ---
Mar. 31, 2014 | Mar. 31, 2013
Segment Reporting Information [Line Items] |  |
Net premiums written | $ 709,892 | $ 689,059
% of Total Net premiums written | 100.00% | 100.00%
Net premiums earned | 519,230 | 488,442
% of Total Net premiums earned | 100.00% | 100.00%
Diversified Reinsurance Segment [Member] |  |
Segment Reporting Information [Line Items] |  |
Net premiums written | 291,619 | 267,610
% of Total Net premiums written | 41.10% | 38.80%
Net premiums earned | 199,316 | 196,249
% of Total Net premiums earned | 38.40% | 40.20%
Diversified Reinsurance Segment [Member] | Property [Member] |  |
Segment Reporting Information [Line Items] |  |
Net premiums written | 62,581 | 69,522
% of Total Net premiums written | 8.80% | 10.10%
Net premiums earned | 40,595 | 47,547
% of Total Net premiums earned | 7.80% | 9.70%
Diversified Reinsurance Segment [Member] | Casualty [Member] |  |
Segment Reporting Information [Line Items] |  |
Net premiums written | 171,754 | 148,423
% of Total Net premiums written | 24.20% | 21.50%
Net premiums earned | 121,887 | 117,059
% of Total Net premiums earned | 23.50% | 24.00%
Diversified Reinsurance Segment [Member] | Accident and Health [Member] |  |
Segment Reporting Information [Line Items] |  |
Net premiums written | 17,222 | 15,529
% of Total Net premiums written | 2.40% | 2.20%
Net premiums earned | 8,886 | 8,633
% of Total Net premiums earned | 1.70% | 1.80%
Diversified Reinsurance Segment [Member] | International [Member] |  |
Segment Reporting Information [Line Items] |  |
Net premiums written | 40,062 | 34,136
% of Total Net premiums written | 5.70% | 5.00%
Net premiums earned | 27,948 | 23,010
% of Total Net premiums earned | 5.40% | 4.70%
AmTrust Quota Share Reinsurance Segment [Member] |  |
Segment Reporting Information [Line Items] |  |
Net premiums written | 419,010 | 344,818
% of Total Net premiums written | 59.00% | 50.10%
Net premiums earned | 304,922 | 220,288
% of Total Net premiums earned | 58.70% | 45.00%
AmTrust Quota Share Reinsurance Segment [Member] | Small Commercial Business [Member] |  |
Segment Reporting Information [Line Items] |  |
Net premiums written | 253,757 | 162,018
% of Total Net premiums written | 35.70% | 23.50%
Net premiums earned | 158,605 | 102,257
% of Total Net premiums earned | 30.50% | 20.90%
AmTrust Quota Share Reinsurance Segment [Member] | Specialty Program [Member] |  |
Segment Reporting Information [Line Items] |  |
Net premiums written | 31,798 | 34,946
% of Total Net premiums written | 4.50% | 5.10%
Net premiums earned | 32,853 | 33,346
% of Total Net premiums earned | 6.30% | 6.80%
AmTrust Quota Share Reinsurance Segment [Member] | Specialty Risk and Extended Warranty [Member] |  |
Segment Reporting Information [Line Items] |  |
Net premiums written | 133,455 | 147,854
% of Total Net premiums written | 18.80% | 21.50%
Net premiums earned | 113,464 | 84,685
% of Total Net premiums earned | 21.90% | 17.30%
NGHC Quota Share Segment [Member] |  |
Segment Reporting Information [Line Items] |  |
Net premiums written | (737) | 76,631
% of Total Net premiums written | (0.10%) | 11.10%
Net premiums earned | 14,992 | 71,905
% of Total Net premiums earned | 2.90% | 14.80%
NGHC Quota Share Segment [Member] | Automobile Liability [Member] |  |
Segment Reporting Information [Line Items] |  |
Net premiums written | (534) | 44,339
% of Total Net premiums written | (0.10%) | 6.40%
Net premiums earned | 9,096 | 41,630
% of Total Net premiums earned | 1.80% | 8.60%
NGHC Quota Share Segment [Member] | Automobile Physical Damage [Member] |  |
Segment Reporting Information [Line Items] |  |
Net premiums written | (203) | 32,292
% of Total Net premiums written | 0.00% | 4.70%
Net premiums earned | $ 5,896 | $ 30,275
% of Total Net premiums earned | 1.10% | 6.20%

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- Definition Amount, after premiums ceded to other entities and premiums assumed by the entity, of premiums earned. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 17 -Article 12 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 235 -Section S99 -Paragraph 2 -Subparagraph (SX 210.12-17) -URI http://asc.fasb.org/extlink&oid=6588446&loc=d3e574992-122915 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04.1) -URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 1 -Article 7 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 605 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6486672&loc=d3e27261-158547 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.13(c)) -URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882 + Details
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- Definition Amount, after premiums ceded to other entities and premiums assumed by the entity, of premiums written. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 17 -Article 12 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 605 -Section 50 -Paragraph 1 -Subparagraph (b),(c) -URI http://asc.fasb.org/extlink&oid=6486672&loc=d3e27261-158547 + Details
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