Intangible Assets (Narrative) (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Goodwill and Intangible Assets Disclosure [Abstract]
Amortization expense relating to all intangible assets	$ 18	$ 13
Amortization expense for remainder of the year	40
Intangible assets amortization expense, year one	34
Intangible assets amortization expense, year two	25
Intangible assets amortization expense, year three	22
Intangible assets amortization expense, year four	17
Intangible assets amortization expense, year five	$ 15