Segment information - Revenue by segment (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Segment Reporting, Revenue Reconciling Item
Revenue	[1]	$ 560,999	$ 549,824	$ 551,385
Owned hotels
Segment Reporting, Revenue Reconciling Item
Revenue		485,882	475,374	472,531
Part owned trains and hotels
Segment Reporting, Revenue Reconciling Item
Revenue		11,924	15,163	13,383
Europe | Owned hotels
Segment Reporting, Revenue Reconciling Item
Revenue		212,379	199,251	200,059
North America | Owned hotels
Segment Reporting, Revenue Reconciling Item
Revenue		149,284	145,868	148,103
Rest of world | Owned hotels
Segment Reporting, Revenue Reconciling Item
Revenue		124,219	130,255	124,369
Owned trains and cruises | Owned trains and cruises
Segment Reporting, Revenue Reconciling Item
Revenue		63,193	59,287	65,471
Part-owned/managed hotels | Part owned trains and hotels
Segment Reporting, Revenue Reconciling Item
Revenue		1,036	4,400	5,232
Part-owned/managed trains | Part owned trains and hotels
Segment Reporting, Revenue Reconciling Item
Revenue		$ 10,888	$ 10,763	$ 8,151

[1] Includes revenue from related parties of $15,449,000, $15,458,000 and $13,123,000, respectively