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Investments - Related Parties - 800 Superior, LLC (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Related Parties \| 800 Superior, LLC
Schedule of Equity Method Investments
Rent expense	$ 761	$ 742
800 Superior, LLC \| AmTrust Financial Services, Inc.
Schedule of Equity Method Investments
Ownership percentage	50.00%
800 Superior, LLC \| VIE, Not primary beneficiary \| Related Parties
Schedule of Equity Method Investments
Ownership percentage	50.00%
Equity investment in unconsolidated subsidiaries	$ 9,487		$ 9,365
Equity in earnings (losses)	$ 122	$ (293)