Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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

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Amount of gain from upward price adjustment on investment in equity security without readily determinable fair value.

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Fair Value Measurements Fair Value Measurements - Non-Recurring Basis (Details) - USD ($)	3 Months Ended			9 Months Ended
	Sep. 30, 2019	Jun. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Fair Value Measurements on a Non-Recurring Basis [Line Items]
Upward adjustment to equity investment		$ 38,000,000
Carrying value of the investment	$ 42,000,000			$ 42,000,000
Nonrecurring
Fair Value Measurements on a Non-Recurring Basis [Line Items]
Asset impairment charges	$ 0		$ 0	$ 0	$ 0