Description of Business, Accounting Policies, and Supplemental Disclosures (Tables)

12 Months Ended

Dec. 31, 2020

Accounting Policies [Abstract]

Supplemental Cash Flow Information

The following table shows supplemental cash flow information (in millions):

	Year Ended December 31,
	2018		2019		2020
SUPPLEMENTAL CASH FLOW INFORMATION:
Cash paid for interest on debt	$	854	$	875	$	916
Cash paid for operating leases	$	—	$	3,361	$	4,475
Cash paid for interest on finance leases	$	381	$	647	$	612
Cash paid for interest on financing obligations	$	194	$	39	$	102
Cash paid for income taxes, net of refunds	$	1,184	$	881	$	1,713
Assets acquired under operating leases	$	—	$	7,870	$	16,217
Property and equipment acquired under finance leases	$	10,615	$	13,723	$	11,588
Property and equipment acquired under build-to-suit arrangements	$	3,641	$	1,362	$	2,267

Schedule of Calculation of Diluted Shares

The following table shows the calculation of diluted shares (in millions):

	Year Ended December 31,
	2018	2019	2020
Shares used in computation of basic earnings per share	487	494	500
Total dilutive effect of outstanding stock awards	13	10	10
Shares used in computation of diluted earnings per share	500	504	510