Additional Accounting Policy and Balance Sheet Disclosures (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Accounting Policies [Abstract]
Equity Method Investments	$ 576	$ 32
Equity Securities, FV-NI, Noncurrent	217
Cost Method Investments	22	28
Alternative Investment	16	0
Foreign Currency Transaction Gain (Loss), before Tax	$ 25	$ 24	$ 52
PPD-SNBL K.K.
Noncontrolling Interest [Line Items]
Noncontrolling Interest, Ownership Percentage by Parent	60.00%
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners	40.00%

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Fair value of investment other than investment in equity security, investment in debt security and equity method investment. Includes, but is not limited to, investment in certain entities that calculate net asset value per share. Example includes, but is not limited to, investment in hedge fund, venture capital fund, private equity fund, and real estate partnership or fund.

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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI), classified as noncurrent.

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Amount of investment in equity security without readily determinable fair value.

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Amount before tax of foreign currency transaction realized and unrealized gain (loss) recognized in the income statement.

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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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The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

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The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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