Fair Value Measurements - Fair Values of Derivative Instruments in Consolidated Balance Sheets (Detail) - Interest Rate Swap Arrangements - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Prepaid Expenses and Other Current Assets
Derivatives Fair Value [Line Items]
Assets	$ 2	$ 3
Other Non- Current Assets
Derivatives Fair Value [Line Items]
Assets	12
Liabilities		20
Other Non-Current Liabilities
Derivatives Fair Value [Line Items]
Liabilities	$ 6	$ 3