Commitments And Contingencies (Minimum Contractual Obligations) (Details) $ in Millions	Dec. 31, 2020 USD ($)
Long-term Purchase Commitment [Line Items]
Unrecorded Total	$ 2,897
Unrecorded Unconditional Purchase Obligation, Due in Remainder of Fiscal Year	82
Unrecorded Unconditional Purchase Obligation, Due in Next Rolling Twelve Months	546
Unrecorded Unconditional Purchase Obligation, Due in Rolling Year Two	545
Unrecorded Unconditional Purchase Obligation, Due in Rolling Year Three	519
Unrecorded Unconditional Purchase Obligation, Due in Rolling Year Four	518
Unrecorded Unconditional Purchase Obligation, Due in Rolling Year Five	393
Unrecorded Unconditional Purchase Obligation, Due in Rolling after Year Five	294
Recorded Total	1,409
Recorded Unconditional Purchase Obligation, Due in Remainder of Fiscal Year	664
Recorded Unconditional Purchase Obligation, Due in Next Rolling Twelve Months	119
Recorded Unconditional Purchase Obligation, Due in Rolling Year Two	47
Recorded Unconditional Purchase Obligation, Due in Rolling Year Three	41
Recorded Unconditional Purchase Obligation, Due in Rolling Year Four	37
Recorded Unconditional Purchase Obligation, Due in Rolling Year Five	432
Recorded Unconditional Purchase Obligation, Due in Rolling after Year Five	69
TotalUnconditionalPurchaseObligationBalanceSheetAmount	4,306
TotalUnconditionalPurchaseObligationBalanceSheetAmountRemainingForCurrentFiscalYear	746
Total Unconditional PurchaseObligationBalanceSheetAmountOneYearAfterFiscalYearEnd	665
Total Unconditional Purchase Obligation Balance Sheet Amount Two Years After Fiscal Year End	592
TotalUnconditionalPurchaseObligationBalanceSheetAmountThreeYearsAfterFiscalYearEnd	560
TotalUnconditionalPurchaseObligationBalanceSheetAmountFourYearsAfterFiscalYearEnd	555
Total Unconditional Purchase Obligation Balance Sheet Amount Five Years After Fiscal Year End	825
TotalUnconditionalPurchaseObligationBalanceSheetAmountThereafter	$ 363
Minimum
Long-term Purchase Commitment [Line Items]
Lessee, Operating Lease, Lease Not yet Commenced, Term of Contract	5 years
Maximum
Long-term Purchase Commitment [Line Items]
Lessee, Operating Lease, Lease Not yet Commenced, Term of Contract	12 years
Developer Commitments
Long-term Purchase Commitment [Line Items]
Unrecorded Total	$ 1,839
Unrecorded Unconditional Purchase Obligation, Due in Remainder of Fiscal Year	31
Unrecorded Unconditional Purchase Obligation, Due in Next Rolling Twelve Months	307
Unrecorded Unconditional Purchase Obligation, Due in Rolling Year Two	367
Unrecorded Unconditional Purchase Obligation, Due in Rolling Year Three	357
Unrecorded Unconditional Purchase Obligation, Due in Rolling Year Four	366
Unrecorded Unconditional Purchase Obligation, Due in Rolling Year Five	273
Unrecorded Unconditional Purchase Obligation, Due in Rolling after Year Five	138
Marketing [Member]
Long-term Purchase Commitment [Line Items]
Unrecorded Total	675
Unrecorded Unconditional Purchase Obligation, Due in Remainder of Fiscal Year	27
Unrecorded Unconditional Purchase Obligation, Due in Next Rolling Twelve Months	151
Unrecorded Unconditional Purchase Obligation, Due in Rolling Year Two	131
Unrecorded Unconditional Purchase Obligation, Due in Rolling Year Three	129
Unrecorded Unconditional Purchase Obligation, Due in Rolling Year Four	117
Unrecorded Unconditional Purchase Obligation, Due in Rolling Year Five	85
Unrecorded Unconditional Purchase Obligation, Due in Rolling after Year Five	35
Senior Notes Interest [Member]
Long-term Purchase Commitment [Line Items]
Unrecorded Total	102
Unrecorded Unconditional Purchase Obligation, Due in Remainder of Fiscal Year	7
Unrecorded Unconditional Purchase Obligation, Due in Next Rolling Twelve Months	20
Unrecorded Unconditional Purchase Obligation, Due in Rolling Year Two	19
Unrecorded Unconditional Purchase Obligation, Due in Rolling Year Three	19
Unrecorded Unconditional Purchase Obligation, Due in Rolling Year Four	19
Unrecorded Unconditional Purchase Obligation, Due in Rolling Year Five	18
Unrecorded Unconditional Purchase Obligation, Due in Rolling after Year Five	0
Operating Lease Imputed Interest [Member] [Member]
Long-term Purchase Commitment [Line Items]
Unrecorded Total	31
Unrecorded Unconditional Purchase Obligation, Due in Remainder of Fiscal Year	2
Unrecorded Unconditional Purchase Obligation, Due in Next Rolling Twelve Months	7
Unrecorded Unconditional Purchase Obligation, Due in Rolling Year Two	5
Unrecorded Unconditional Purchase Obligation, Due in Rolling Year Three	4
Unrecorded Unconditional Purchase Obligation, Due in Rolling Year Four	3
Unrecorded Unconditional Purchase Obligation, Due in Rolling Year Five	2
Unrecorded Unconditional Purchase Obligation, Due in Rolling after Year Five	8
Other Unrecorded Purchase Obligations [Member]
Long-term Purchase Commitment [Line Items]
Unrecorded Total	99
Unrecorded Unconditional Purchase Obligation, Due in Remainder of Fiscal Year	15
Unrecorded Unconditional Purchase Obligation, Due in Next Rolling Twelve Months	59
Unrecorded Unconditional Purchase Obligation, Due in Rolling Year Two	20
Unrecorded Unconditional Purchase Obligation, Due in Rolling Year Three	3
Unrecorded Unconditional Purchase Obligation, Due in Rolling Year Four	1
Unrecorded Unconditional Purchase Obligation, Due in Rolling Year Five	1
Unrecorded Unconditional Purchase Obligation, Due in Rolling after Year Five	0
Senior Notes Principal And Interest [Member]
Long-term Purchase Commitment [Line Items]
Recorded Total	1,014
Recorded Unconditional Purchase Obligation, Due in Remainder of Fiscal Year	614
Recorded Unconditional Purchase Obligation, Due in Next Rolling Twelve Months	0
Recorded Unconditional Purchase Obligation, Due in Rolling Year Two	0
Recorded Unconditional Purchase Obligation, Due in Rolling Year Three	0
Recorded Unconditional Purchase Obligation, Due in Rolling Year Four	0
Recorded Unconditional Purchase Obligation, Due in Rolling Year Five	400
Recorded Unconditional Purchase Obligation, Due in Rolling after Year Five	0
Operating Lease [Member]
Long-term Purchase Commitment [Line Items]
Unrecorded Total	151
Unrecorded Unconditional Purchase Obligation, Due in Remainder of Fiscal Year	0
Unrecorded Unconditional Purchase Obligation, Due in Next Rolling Twelve Months	2
Unrecorded Unconditional Purchase Obligation, Due in Rolling Year Two	3
Unrecorded Unconditional Purchase Obligation, Due in Rolling Year Three	7
Unrecorded Unconditional Purchase Obligation, Due in Rolling Year Four	12
Unrecorded Unconditional Purchase Obligation, Due in Rolling Year Five	14
Unrecorded Unconditional Purchase Obligation, Due in Rolling after Year Five	113
Recorded Total	295
Recorded Unconditional Purchase Obligation, Due in Remainder of Fiscal Year	21
Recorded Unconditional Purchase Obligation, Due in Next Rolling Twelve Months	68
Recorded Unconditional Purchase Obligation, Due in Rolling Year Two	44
Recorded Unconditional Purchase Obligation, Due in Rolling Year Three	37
Recorded Unconditional Purchase Obligation, Due in Rolling Year Four	31
Recorded Unconditional Purchase Obligation, Due in Rolling Year Five	25
Recorded Unconditional Purchase Obligation, Due in Rolling after Year Five	69
Transition And Other Taxes [Member]
Long-term Purchase Commitment [Line Items]
Recorded Total	66
Recorded Unconditional Purchase Obligation, Due in Remainder of Fiscal Year	22
Recorded Unconditional Purchase Obligation, Due in Next Rolling Twelve Months	24
Recorded Unconditional Purchase Obligation, Due in Rolling Year Two	3
Recorded Unconditional Purchase Obligation, Due in Rolling Year Three	4
Recorded Unconditional Purchase Obligation, Due in Rolling Year Four	6
Recorded Unconditional Purchase Obligation, Due in Rolling Year Five	7
Recorded Unconditional Purchase Obligation, Due in Rolling after Year Five	0
License obligations [Member]
Long-term Purchase Commitment [Line Items]
Recorded Total	34
Recorded Unconditional Purchase Obligation, Due in Remainder of Fiscal Year	7
Recorded Unconditional Purchase Obligation, Due in Next Rolling Twelve Months	27
Recorded Unconditional Purchase Obligation, Due in Rolling Year Two	0
Recorded Unconditional Purchase Obligation, Due in Rolling Year Three	0
Recorded Unconditional Purchase Obligation, Due in Rolling Year Four	0
Recorded Unconditional Purchase Obligation, Due in Rolling Year Five	0
Recorded Unconditional Purchase Obligation, Due in Rolling after Year Five	$ 0