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Investments - Related Parties - 800 Superior, LLC (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Related Parties \| 800 Superior, LLC
Schedule of Equity Method Investments
Rent expense	$ 762	$ 742	$ 1,523	$ 1,484
800 Superior, LLC \| AmTrust Financial Services, Inc.
Schedule of Equity Method Investments
Ownership percentage	50.00%		50.00%
800 Superior, LLC \| VIE, Not primary beneficiary \| Related Parties
Schedule of Equity Method Investments
Equity investment in unconsolidated subsidiaries	$ 9,466		$ 9,466		$ 9,365
Equity in earnings (losses)	$ (21)	$ 309	$ 101	$ 16
800 Superior, LLC \| VIE, Not primary beneficiary \| Related Parties \| AmTrust Financial Services, Inc.
Schedule of Equity Method Investments
Ownership percentage	50.00%		50.00%