Income Taxes - Summary of Temporary Differences of Deferred Tax Assets and Liabilities (Parenthetical) (Details) $ in Millions	Sep. 30, 2020 USD ($)
Tax Credit Carryforward [Line Items]
Goodwill expected to be deductible for tax purposes	$ 5
Foreign Tax Authority [Member]
Tax Credit Carryforward [Line Items]
Operating Loss Carryforwards	145
Tax credits	12
State and Local Jurisdiction [Member]
Tax Credit Carryforward [Line Items]
Operating Loss Carryforwards	1,000
Operating loss carryforwards expiring in next fiscal year	64
Operating loss carryforwards expiring in fiscal year two	$ 121