Goodwill - Changes in carrying amount of goodwill (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2017	Dec. 31, 2016
Goodwill
Gross goodwill amount	$ 167,146	$ 157,466
Accumulated impairment	(44,123)	(44,123)
Net goodwill amount	123,023	113,343
Goodwill on acquisition	5,500
Changes in the carrying amount of goodwill
Impairment	0
Foreign currency translation adjustment	4,180
Owned trains and cruises
Goodwill
Gross goodwill amount	6,766	6,325
Accumulated impairment	(662)	(662)
Net goodwill amount	6,104	5,663
Goodwill on acquisition	0
Changes in the carrying amount of goodwill
Impairment	0
Foreign currency translation adjustment	441
Owned hotels - Europe \| Total owned hotels
Goodwill
Gross goodwill amount	68,250	64,459
Accumulated impairment	(14,202)	(14,202)
Net goodwill amount	54,048	50,257
Goodwill on acquisition	0
Changes in the carrying amount of goodwill
Impairment	0
Foreign currency translation adjustment	3,791
Owned hotels - North America \| Total owned hotels
Goodwill
Gross goodwill amount	71,601	66,101
Accumulated impairment	(16,110)	(16,110)
Net goodwill amount	55,491	49,991
Goodwill on acquisition	5,500
Changes in the carrying amount of goodwill
Impairment	0
Foreign currency translation adjustment	0
Owned hotels - Rest of world \| Total owned hotels
Goodwill
Gross goodwill amount	20,529	20,581
Accumulated impairment	(13,149)	(13,149)
Net goodwill amount	7,380	$ 7,432
Goodwill on acquisition	0
Changes in the carrying amount of goodwill
Impairment	0
Foreign currency translation adjustment	$ (52)

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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