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v3.19.1

Fair Value Measurements (Narrative) (Details) $ / shares in Units, shares in Millions, $ in Millions, £ in Billions |  |  | 1 Months Ended | 3 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | --- | ---
Apr. 01, 2019 GBP (£) | Sep. 20, 2018 GBP (£) | Apr. 26, 2019 USD ($) | Mar. 31, 2019 USD ($) $ / shares shares | Mar. 31, 2019 USD ($) $ / shares shares | Sep. 30, 2018 USD ($) | Mar. 31, 2018 USD ($) | Mar. 31, 2019 R / shares | Dec. 31, 2018 USD ($) | Dec. 31, 2014 R / shares
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |  |  |  |  |
Total consideration |  |  |  |  | $ 177 |  | $ 36 |  |  |
Net charge for adjustments related to acquisition related accounts |  |  |  |  | 11 |  | 5 |  |  |
Increase in fair value of contingent consideration due to 5% increase in projections |  |  |  |  | 44 |  |  |  |  |
Decrease in fair value of contingent consideration due to 5% decrease in projections |  |  |  |  | 36 |  |  |  |  |
Carrying value of investment |  |  |  | $ 388 | 388 |  |  |  | $ 287 |
Equity method income |  |  |  |  | 2 |  | 7 |  |  |
Other investments |  |  |  | 74 | $ 74 |  |  |  | 75 |
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] |  |  |  |  |  |  |  |  |  |
Carrying value of investment |  |  |  | 155 | $ 155 |  |  |  | 61 |
Private Equity Funds, Non-US |  |  |  |  |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |  |  |  |  |
Carrying value of investment |  |  |  | 84 | 84 |  |  |  | 82 |
Equity Securities |  |  |  |  |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |  |  |  |  |
Investments, fair value |  |  |  | $ 35 | $ 35 |  |  |  | 146 |
Alexander Forbes Group Holdings Limited |  |  |  |  |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |  |  |  |  |
Share price (per share amount) | R / shares |  |  |  |  |  |  |  | R 5.03 |  | R 7.50
Percentage of ownership in equity investment |  |  |  | 33.00% | 33.00% |  |  |  |  |
Carrying value of investment |  |  |  | $ 149 | $ 149 |  |  |  |  |
Other than temporary impairment |  |  |  |  |  | $ 83 |  |  |  |
Shares owned in investment (in shares) | shares |  |  |  | 443 | 443 |  |  |  |  |
Equity method investment, quoted market value |  |  |  | $ 157 | $ 157 |  |  |  |  |
Benefitfocus |  |  |  |  |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |  |  |  |  |
Unrealized investment (losses) gains |  |  |  |  | 3 |  | $ (8) |  |  |
Proceeds from sale of other investments |  |  |  | $ 132 | $ 115 |  |  |  |  |
Jardine Lloyd Thompson Group plc |  |  |  |  |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |  |  |  |  |
Total consideration | £ |  | £ 5.2 |  |  |  |  |  |  |  |
Treasury Lock | Jardine Lloyd Thompson Group plc |  |  |  |  |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |  |  |  |  |
Derivative hedges, assets |  |  |  |  |  |  |  |  | $ 2,000 |
Money Market Funds |  |  |  |  |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |  |  |  |  |
Share price (per share amount) | $ / shares |  |  |  | $ 1.00 | $ 1.00 |  |  |  |  |
Subsequent Event | Benefitfocus |  |  |  |  |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |  |  |  |  |
Proceeds from sale of other investments |  |  | $ 17 |  |  |  |  |  |  |
Subsequent Event | Jardine Lloyd Thompson Group plc |  |  |  |  |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |  |  |  |  |
Total consideration | £ | £ 5.2 |  |  |  |  |  |  |  |  |

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