Income Taxes (Narrative) (Details)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Before Income Tax Domestic And Foreign [Line Items]
Statutory tax rate	7.80%	7.80%	7.80%
Switzerland
Income Before Income Tax Domestic And Foreign [Line Items]
Statutory tax rate	7.80%
Bermuda
Income Before Income Tax Domestic And Foreign [Line Items]
Statutory tax rate	0.00%
Percentage of income before income taxes	137.00%	181.00%	88.00%
United States
Income Before Income Tax Domestic And Foreign [Line Items]
Statutory tax rate	35.00%
Canada
Income Before Income Tax Domestic And Foreign [Line Items]
Statutory tax rate	15.00%
HONG KONG
Income Before Income Tax Domestic And Foreign [Line Items]
Statutory tax rate	16.50%
Ireland
Income Before Income Tax Domestic And Foreign [Line Items]
Statutory tax rate	12.50%
SINGAPORE
Income Before Income Tax Domestic And Foreign [Line Items]
Statutory tax rate	17.00%
United Kingdom
Income Before Income Tax Domestic And Foreign [Line Items]
Statutory tax rate	20.00%