Fair Value Measurement (Tables)

12 Months Ended

Dec. 31, 2019

Fair Value Disclosures [Abstract]

Schedule of Assets and Liabilities Measured at Fair Value on Recurring Basis

The following table summarizes our assets measured at fair value and the classification by level of input within the fair value hierarchy (in millions):



						Fair Value Measurement at Reporting Date Using
Description		December 31, 2019				Quoted Prices in Active Markets for Identical Assets (Level 1)				Significant Other Observable Inputs (Level 2)				Significant Unobservable Inputs (Level 3)
Cash equivalents:
Money market funds		$	12,787			$	12,787			$	—			$	—
U.S. government securities		815				815				—				—
U.S. government agency securities		444				444				—				—
Certificate of deposits and time deposits		217				—				217				—
Corporate debt securities		81				—				81				—
Marketable securities:
U.S. government securities		18,679				18,679				—				—
U.S. government agency securities		6,712				6,712				—				—
Corporate debt securities		10,385				—				10,385				—
Total cash equivalents and marketable securities		$	50,120			$	39,437			$	10,683			$	—



						Fair Value Measurement at Reporting Date Using
Description		December 31, 2018				Quoted Prices in Active Markets for Identical Assets (Level 1)				Significant Other Observable Inputs (Level 2)				Significant Unobservable Inputs (Level 3)
Cash equivalents:
Money market funds		$	6,792			$	6,792			$	—			$	—
U.S. government securities		90				90				—				—
U.S. government agency securities		54				54				—				—
Certificate of deposits and time deposits		369				—				369				—
Corporate debt securities		1				—				1				—
Marketable securities:
U.S. government securities		13,836				13,836				—				—
U.S. government agency securities		8,333				8,333				—				—
Corporate debt securities		8,926				—				8,926				—
Total cash equivalents and marketable securities		$	38,401			$	29,105			$	9,296			$	—