Income Tax Reconciliation, Change To Deferred Taxes Related to Unrealized Foreign Exchange Net of Valuation Allowance

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- Definition

Unrecognized Tax Benefits That Would Not Impact Effective Tax Rate

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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-Publisher FASB

-Name Accounting Standards Codification

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

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Amount of expense for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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Taxation (Narrative) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Tax Examination [Line Items]
Valuation allowance	$ 17	$ 17	$ 64
Unrecognized tax benefits that would not affect the effective tax rate	17	17	22
Unrecognized tax benefits that would affect the effective tax rate	6	6	5
Tax-related interest and penalties reported in the consolidated statements of operations		(1)	(1)	(8)
Liabilities recorded for tax-related interest and penalties	9	9	11
Income Tax Reconciliation, Change To Deferred Taxes Related to Unrealized Foreign Exchange Net	89	71
Domestic Tax Authority [Member]
Income Tax Examination [Line Items]
Net operating loss carry-forwards	113	113
Switzerland
Income Tax Examination [Line Items]
Applicable income tax rates		7.83%
Foreign Tax Authority [Member]
Income Tax Examination [Line Items]
Foreign tax credit carry-forward	$ 129	$ 129
Bermuda
Income Tax Examination [Line Items]
Applicable income tax rates		0.00%
U.S.
Income Tax Examination [Line Items]
Applicable income tax rates		35.00%
U.K.
Income Tax Examination [Line Items]
Applicable income tax rates		21.50%