Commitments And Contingencies (Minimum Contractual Obligations) (Details) $ in Millions	Mar. 31, 2021 USD ($)
Long Term Purchase Commitments
Unrecorded Unconditional Purchase Obligation	$ 3,922
Unrecorded Unconditional Purchase Obligation, Due in Next Rolling Twelve Months	567
Unrecorded Unconditional Purchase Obligation, Due in Rolling Year Two	623
Unrecorded Unconditional Purchase Obligation, Due in Rolling Year Three	697
Unrecorded Unconditional Purchase Obligation, Due in Rolling Year Four	577
Unrecorded Unconditional Purchase Obligation, Due in Rolling Year Five	451
Unrecorded Unconditional Purchase Obligation, Due in Rolling after Year Five	1,007
Recorded Unconditional Purchase Obligation	2,256
Recorded Unconditional Purchase Obligation, Due in Next Rolling Twelve Months	107
Recorded Unconditional Purchase Obligation, Due in Rolling Year Two	69
Recorded Unconditional Purchase Obligation, Due in Rolling Year Three	42
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	1,569
TotalUnconditionalPurchaseObligationBalanceSheetAmount	6,178
Total Unconditional Purchase Obligation Balance Sheet Amount One Year After Fiscal Year End	674
TotalUnconditionalPurchaseObligationBalanceSheetAmountTwoYearsAfterFiscalYearEnd	692
TotalUnconditionalPurchaseObligationBalanceSheetAmountThreeYearsAfterFiscalYearEnd	739
Total Unconditional Purchase Obligation Balance Sheet Amount Four Years After Fiscal Year End	614
TotalUnconditionalPurchaseObligationBalanceSheetAmountFiveYearsAfterFiscalYearEnd	883
TotalUnconditionalPurchaseObligationBalanceSheetAmountThereafter	2,576
Developer Commitments [Member]
Long Term Purchase Commitments
Unrecorded Unconditional Purchase Obligation	1,945
Unrecorded Unconditional Purchase Obligation, Due in Next Rolling Twelve Months	297
Unrecorded Unconditional Purchase Obligation, Due in Rolling Year Two	377
Unrecorded Unconditional Purchase Obligation, Due in Rolling Year Three	377
Unrecorded Unconditional Purchase Obligation, Due in Rolling Year Four	387
Unrecorded Unconditional Purchase Obligation, Due in Rolling Year Five	294
Unrecorded Unconditional Purchase Obligation, Due in Rolling after Year Five	213
Marketing
Long Term Purchase Commitments
Unrecorded Unconditional Purchase Obligation	671
Unrecorded Unconditional Purchase Obligation, Due in Next Rolling Twelve Months	157
Unrecorded Unconditional Purchase Obligation, Due in Rolling Year Two	136
Unrecorded Unconditional Purchase Obligation, Due in Rolling Year Three	130
Unrecorded Unconditional Purchase Obligation, Due in Rolling Year Four	122
Unrecorded Unconditional Purchase Obligation, Due in Rolling Year Five	86
Unrecorded Unconditional Purchase Obligation, Due in Rolling after Year Five	40
Senior Notes Interest
Long Term Purchase Commitments
Unrecorded Unconditional Purchase Obligation	897
Unrecorded Unconditional Purchase Obligation, Due in Next Rolling Twelve Months	56
Unrecorded Unconditional Purchase Obligation, Due in Rolling Year Two	55
Unrecorded Unconditional Purchase Obligation, Due in Rolling Year Three	55
Unrecorded Unconditional Purchase Obligation, Due in Rolling Year Four	55
Unrecorded Unconditional Purchase Obligation, Due in Rolling Year Five	54
Unrecorded Unconditional Purchase Obligation, Due in Rolling after Year Five	622
Operating Lease Imputed Interest [Member] [Member]
Long Term Purchase Commitments
Unrecorded Unconditional Purchase Obligation	30
Unrecorded Unconditional Purchase Obligation, Due in Next Rolling Twelve Months	7
Unrecorded Unconditional Purchase Obligation, Due in Rolling Year Two	6
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
Operating Lease [Member]
Long Term Purchase Commitments
Unrecorded Unconditional Purchase Obligation	163
Unrecorded Unconditional Purchase Obligation, Due in Next Rolling Twelve Months	3
Unrecorded Unconditional Purchase Obligation, Due in Rolling Year Two	6
Unrecorded Unconditional Purchase Obligation, Due in Rolling Year Three	7
Unrecorded Unconditional Purchase Obligation, Due in Rolling Year Four	9
Unrecorded Unconditional Purchase Obligation, Due in Rolling Year Five	14
Unrecorded Unconditional Purchase Obligation, Due in Rolling after Year Five	124
Recorded Unconditional Purchase Obligation	278
Recorded Unconditional Purchase Obligation, Due in Next Rolling Twelve Months	49
Recorded Unconditional Purchase Obligation, Due in Rolling Year Two	66
Recorded Unconditional Purchase Obligation, Due in Rolling Year Three	38
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
Other Unrecorded Purchase Obligations [Member]
Long Term Purchase Commitments
Unrecorded Unconditional Purchase Obligation	216
Unrecorded Unconditional Purchase Obligation, Due in Next Rolling Twelve Months	47
Unrecorded Unconditional Purchase Obligation, Due in Rolling Year Two	43
Unrecorded Unconditional Purchase Obligation, Due in Rolling Year Three	124
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 Commitments
Recorded Unconditional Purchase Obligation	1,907
Recorded Unconditional Purchase Obligation, Due in Next Rolling Twelve Months	7
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	1,500
Transition And Other Taxes [Member]
Long Term Purchase Commitments
Recorded Unconditional Purchase Obligation	44
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 Commitments
Recorded Unconditional Purchase Obligation	27
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