COVID-19 Pandemic, CARES Funding (Details) - USD ($) $ in Millions	3 Months Ended		11 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2021	Apr. 29, 2021
CARES Funds Received [Line Items]
Total Expected Relief From PSP of CARES Act			$ 2,268
Adjustments to Additional Paid in Capital, Warrant Issued			24
Total Unsecured Term Loan through PSP of CARES Act			599
CARES Act Payroll Tax Relief	$ 8
ProceedsFromPayrollSupportProgramGrant			1,645
PSPGrantRecognized	411	$ 0
CARES PSP 1 [Member]
CARES Funds Received [Line Items]
Total Expected Relief From PSP of CARES Act			1,059
Adjustments to Additional Paid in Capital, Warrant Issued			9
Total Unsecured Term Loan through PSP of CARES Act			293
ProceedsFromPayrollSupportProgramGrant			757
PSP Installments Received	8
CARES PSP 2 [Member]
CARES Funds Received [Line Items]
Total Expected Relief From PSP of CARES Act			625
Adjustments to Additional Paid in Capital, Warrant Issued	8		9
Total Unsecured Term Loan through PSP of CARES Act	136		159
ProceedsFromPayrollSupportProgramGrant	403		457
PSP Installments Received	$ 539
CARES PSP 2 [Member] | Subsequent Event [Member]
CARES Funds Received [Line Items]
Additional Relief from PSP of CARES Act				$ 80
CARES PSP 3 [Member]
CARES Funds Received [Line Items]
Total Expected Relief From PSP of CARES Act			584
Adjustments to Additional Paid in Capital, Warrant Issued			6
Total Unsecured Term Loan through PSP of CARES Act			147
ProceedsFromPayrollSupportProgramGrant			$ 431