Concentration Risk, Collateralized, Percentage

No definition available.

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- Definition

Aggregate dividends declared during the period for each share of common stock outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=64851502&loc=d3e6351-108592

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13531-108611

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=64851502&loc=d3e6404-108592

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 21
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13537-108611

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount of direct and assumed premiums written.

+ References

Reference 1: 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

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Commitments and Contingencies (Details) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended		9 Months Ended		12 Months Ended
	Aug. 03, 2017	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Loss Contingencies [Line Items]
Gross premiums written		$ 630,972	$ 706,854	$ 2,259,597	$ 2,259,290
Dividends declared per common share (in dollars per share)	$ 0.15	$ 0.15	$ 0.14	$ 0.45	$ 0.42
AmTrust Reinsurance segment [Member]
Loss Contingencies [Line Items]
Gross premiums written		$ 420,019	$ 520,104	$ 1,575,677	$ 1,591,902
Segment concentration risk [Member] \| Gross premiums written [Member] \| AmTrust Reinsurance segment [Member]
Loss Contingencies [Line Items]
Concentration risk, percentage		66.60%	73.60%	69.70%	70.50%
Major customer one [Member] \| Customer concentration risk [Member] \| Reinsurance Recoverable [Member]
Loss Contingencies [Line Items]
Concentration risk, percentage				44.70%		54.80%
Major customer two [Member] \| Customer concentration risk [Member] \| Reinsurance Recoverable [Member]
Loss Contingencies [Line Items]
Concentration risk, percentage				15.70%		31.60%
Major customer three [Member] \| Customer concentration risk [Member] \| Reinsurance Recoverable [Member]
Loss Contingencies [Line Items]
Concentration risk, percentage				14.60%		2.90%
Rating A or better [Member] \| Customer concentration risk [Member] \| Reinsurance Recoverable [Member]
Loss Contingencies [Line Items]
Concentration risk, percentage				98.70%		97.20%
Rating B Plus Plus or lower [Member] \| Customer concentration risk [Member] \| Reinsurance Recoverable [Member]
Loss Contingencies [Line Items]
Concentration risk, percentage				1.30%		2.80%
Concentration risk, collateralized, percentage				89.10%		98.60%