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Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income.

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Commitments and Contingencies (Details) - USD ($)	12 Months Ended
Commitments and Contingencies (Details) - USD ($)	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Jul. 01, 2017
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
Contingent consideration, liability	$ 8,903,000	$ 7,419,000
Office leases
Operating Leased Assets [Line Items]
Rent expense	10,500,000	$ 13,700,000	$ 5,600,000
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
2019	9,380,000
2020	9,007,000
2021	8,617,000
2022	7,602,000
2023	7,045,000
2024 and thereafter	29,615,000
Total	$ 71,266,000
THL Hotel Portfolio \| Maximum
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
Contingent consideration, liability				$ 13,000,000.0