Segment information Revenues and long-lived assets by location of property (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	$ 594,081	$ 538,952	$ 549,355
Property, plant and equipment	1,121,749	1,138,114
Bermuda
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	0	0	0
Property, plant and equipment	0	0
Italy
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	133,806	120,307	124,632
Property, plant and equipment	381,718	369,756
United Kingdom
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	65,865	67,647	71,313
Property, plant and equipment	63,964	64,047
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	108,167	85,890	83,126
Property, plant and equipment	342,168	318,672
Brazil
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	80,537	74,731	82,181
Property, plant and equipment	148,012	147,408
All other countries
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	205,706	190,377	188,103
Property, plant and equipment	373,741	422,024
Consolidated entity including consolidated VIE
Revenues from External Customers and Long-Lived Assets [Line Items]
Property, plant and equipment	$ 1,309,603	$ 1,321,907