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Decrease in Fair Value of Contingent Consideration Due to 5% Decrease in Projections

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Fair Value, Level 1 To Level 2 Transfers Assets or Liabilities, Amount

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Increase in Fair Value of Contingent Consideration Due to 5% Increase in Projections

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Carrying amount as of the balance sheet date of the asset arising from derivative instruments and hedging activities, which are expected to be converted into cash or otherwise disposed of within a year or the normal operating cycle, if longer.

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of gain (loss) recognized on the income statement for financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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- Definition

Price of a single share of a number of saleable stocks of a company.

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Fair Value Measurements (Narrative) (Details) $ / shares in Units, £ in Billions		12 Months Ended
	Sep. 18, 2018 GBP (£)	Dec. 31, 2018 USD ($) $ / shares	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2018 R / shares
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total consideration		$ 1,040,000,000	$ 777,000,000
Assets transferred between Level 1 and Level 2		0
Net charge for adjustments related to acquisitions		32,000,000	3,000,000	$ 9,000,000
Increase in fair value of contingent consideration due to 5% increase in projections		43,000,000
Decrease in fair value of contingent consideration due to 5% decrease in projections		35,000,000
Equity method investments		$ 287,000,000	405,000,000
Minimum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Revenue target period (in years)		2 years
Maximum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Revenue target period (in years)		4 years
Private Insurance and Consulting
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity method investments		$ 61,000,000	63,000,000
Private Equity Funds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity method investments		$ 82,000,000	$ 76,000,000
Money Market Funds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Share price (Rand) \| $ / shares		$ 1.00
Jardine Lloyd Thompson Group plc
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total consideration \| £	£ 5.2
Alexander Forbes Group Holdings Limited
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Share price (Rand) \| R / shares					R 5.14
Equity method investments		$ 144,000,000
Treasury Lock \| Jardine Lloyd Thompson Group plc
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative hedge, asset		$ 2,000,000,000