Hotel Management Agreements and Leases - Narrative and Marriott No. 1 (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Mar. 31, 2018 USD ($) Agreement agreement hotel travelcenter	Mar. 31, 2017 USD ($)	Dec. 31, 2018 USD ($)
Management Agreements and Leases [Line Items]
Number of operating agreements | agreement	14
Capital improvements from leased facilities, funded | $	$ 26,483	$ 32,731
Hotel
Management Agreements and Leases [Line Items]
Number of properties owned | hotel	323
Number of operating agreements | Agreement	9
Number of properties leased to taxable REIT subsidiaries | hotel	320
Number of properties leased to third parties | hotel	3
Hotel | Marriott No. 1 agreement
Management Agreements and Leases [Line Items]
Number of properties owned | hotel	53
Operating agreement annual rent and return | $	$ 69,249
Realized returns and rents | $	16,083	$ 17,188
Capital improvements from leased facilities, funded | $	$ 177
Percentage increase In minimum returns after funding for capital improvements	10.00%
Travel centers
Management Agreements and Leases [Line Items]
Number of properties owned | travelcenter	199
Forecast | Hotel | Marriott No. 1 agreement
Management Agreements and Leases [Line Items]
Capital improvements from leased facilities, funded | $			$ 10,900
Minimum | Hotel
Management Agreements and Leases [Line Items]
Number of real estate properties leased or managed | hotel	1
Hotel management agreements and leases, renewal period	20 years
Maximum | Hotel
Management Agreements and Leases [Line Items]
Hotel management agreements and leases, renewal period	60 years