Management Agreements and Leases - Sonesta (Details) $ in Thousands	3 Months Ended			9 Months Ended		12 Months Ended
	Dec. 31, 2018 USD ($)	Sep. 30, 2018 USD ($) hotel	Sep. 30, 2017 USD ($)	Sep. 30, 2018 USD ($) hotel	Sep. 30, 2017 USD ($)	Dec. 31, 2019 USD ($)
Management Agreements and Leases [Line Items]
Capital improvements from leased facilities, funded				$ 111,248	$ 89,955
Hotel | Sonesta agreements
Management Agreements and Leases [Line Items]
Operating agreement annual rent and return				123,180
Realized returns and rents		$ 21,732	$ 18,741	61,606	53,808
Related party transaction, management marketing and reservation system fees		9,437	7,432	26,245	20,719
Procurement and construction supervision fees		713	479	1,907	673
Capital improvements from leased facilities, funded				64,032	21,892
Increase in annual minimum returns				$ 3,948	742
Percentage increase in minimum returns				8.00%
Forecast | Hotel | Sonesta agreements
Management Agreements and Leases [Line Items]
Capital improvements from leased facilities, funded	$ 26,900					$ 79,100
Sonesta Int'l Hotels Corp | Hotel
Management Agreements and Leases [Line Items]
Due to related party, reimbursement of capital expenditures and other		$ 6,735	$ 5,685	$ 6,735	$ 5,685
Sonesta Int'l Hotels Corp | Full service hotel | Hotel
Management Agreements and Leases [Line Items]
Number of real estate properties leased or managed | hotel		11		11
Sonesta Int'l Hotels Corp | Limited services hotel | Hotel
Management Agreements and Leases [Line Items]
Number of real estate properties leased or managed | hotel		39		39