Other intangible assets (Details) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011	Dec. 31, 2011
Carrying amount:
Balance at beginning of period			$ 22,169,000
Foreign currency translation adjustment			(376,000)
Balance at end of period	21,793,000		21,793,000
Accumulated amortization:
Balance at beginning of period			2,704,000
Charge for the year			368,000
Foreign currency translation adjustment			(41,000)
Balance at end of period	3,031,000		3,031,000
Net book value:
Net book value	18,762,000		18,762,000		19,465,000
Other information
Amortization expense	124,000	236,000	368,000	376,000
Estimated amortization expense
2012			496,000
2013			496,000
2014			496,000
2015			496,000
2016			496,000
2017			496,000
Trade names
Carrying amount:
Balance at beginning of period			7,100,000
Foreign currency translation adjustment			0
Balance at end of period	7,100,000		7,100,000
Accumulated amortization:
Balance at beginning of period			0
Charge for the year			0
Foreign currency translation adjustment			0
Balance at end of period	0		0
Net book value:
Carrying amount	7,100,000		7,100,000		7,100,000
Favorable lease assets
Carrying amount:
Balance at beginning of period			13,460,000
Foreign currency translation adjustment			(438,000)
Balance at end of period	13,022,000		13,022,000
Accumulated amortization:
Balance at beginning of period			1,972,000
Charge for the year			267,000
Foreign currency translation adjustment			(70,000)
Balance at end of period	2,169,000		2,169,000
Net book value:
Net book value	10,853,000		10,853,000		11,488,000
Other information
Amortization period, minimum (in years)			19
Amortization period, maximum (in years)			60
Internet sites
Carrying amount:
Balance at beginning of period			1,609,000
Foreign currency translation adjustment			62,000
Balance at end of period	1,671,000		1,671,000
Accumulated amortization:
Balance at beginning of period			732,000
Charge for the year			101,000
Foreign currency translation adjustment			29,000
Balance at end of period	862,000		862,000
Net book value:
Net book value	$ 809,000		$ 809,000		$ 877,000
Other information
Amortization period, maximum (in years)			10