v3.19.2

Segment Information - Net Premiums (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Segment Reporting, Revenue Reconciling Item [Line Items]
Net premiums written	$ (409)	$ 521,028	$ (561,939)	$ 1,143,679
Net premiums earned	133,986	504,388	317,088	1,021,201
Operating segments | Diversified Reinsurance
Segment Reporting, Revenue Reconciling Item [Line Items]
Net premiums written	8,718	29,717	23,665	77,988
Net premiums earned	22,472	28,539	47,764	54,054
Operating segments | Diversified Reinsurance | International
Segment Reporting, Revenue Reconciling Item [Line Items]
Net premiums written	8,718	29,717	23,665	77,947
Net premiums earned	22,472	28,539	47,764	54,013
Operating segments | Diversified Reinsurance | Other
Segment Reporting, Revenue Reconciling Item [Line Items]
Net premiums written			0	41
Net premiums earned	0	0	0	41
Operating segments | AmTrust Reinsurance
Segment Reporting, Revenue Reconciling Item [Line Items]
Net premiums written	(9,127)	491,311	(585,604)	1,065,691
Net premiums earned	111,514	475,849	269,324	967,147
Operating segments | AmTrust Reinsurance | Small Commercial Business
Segment Reporting, Revenue Reconciling Item [Line Items]
Net premiums written	5,515	279,486	(337,166)	647,240
Net premiums earned	23,283	293,514	62,738	609,223
Operating segments | AmTrust Reinsurance | Specialty Program
Segment Reporting, Revenue Reconciling Item [Line Items]
Net premiums written	(16,031)	103,196	(28,639)	192,327
Net premiums earned	30,326	96,739	106,547	185,233
Operating segments | AmTrust Reinsurance | Specialty Risk and Extended Warranty
Segment Reporting, Revenue Reconciling Item [Line Items]
Net premiums written	1,389	108,629	(219,799)	226,124
Net premiums earned	$ 57,905	$ 85,596	$ 100,039	$ 172,691

X

- 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/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(1))
-URI http://asc.fasb.org/extlink&oid=116637232&loc=SL114874131-224263

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 235
-Section S99
-Paragraph 2
-Subparagraph (SX 210.12-17(Column E))
-URI http://asc.fasb.org/extlink&oid=34713774&loc=d3e574992-122915

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(13)(c))
-URI http://asc.fasb.org/extlink&oid=116637391&loc=SL114874048-224260

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 605
-Section 50
-Paragraph 1
-Subparagraph (c)(3)
-URI http://asc.fasb.org/extlink&oid=6486672&loc=d3e27261-158547

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Amount, after premiums ceded to other entities and premiums assumed by the entity, of premiums written.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 605
-Section 50
-Paragraph 1
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=6486672&loc=d3e27261-158547

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-Publisher FASB
-Name Accounting Standards Codification
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