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Investments - Related Parties - 800 Superior, LLC (Details) - Related Parties - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
800 Superior, LLC
Schedule of Equity Method Investments
Rent expense	$ 761	$ 742	$ 2,284	$ 2,226
800 Superior, LLC \| VIE, Not primary beneficiary
Schedule of Equity Method Investments
Equity investment in unconsolidated subsidiaries	9,559		9,559		$ 9,365
Equity in earnings (losses)	93	(103)	194	(87)
Payments to Acquire Equity Method Investments	$ 0	$ 2,287	$ 0	$ 2,287
800 Superior, LLC \| VIE, Not primary beneficiary \| AmTrust Financial Services, Inc.
Schedule of Equity Method Investments
Ownership percentage	50.00%		50.00%