Leases - Supplemental Balance Sheet Information Related to Leases (Detail) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2019	Jan. 01, 2019	Dec. 31, 2018
Operating leases
Operating lease right-of-use assets	$ 425	$ 500
Total operating lease liabilities	503	$ 600
Finance leases
Property, plant and equipment, net	423		$ 468
Other intangible assets, gross	6,761		6,693
Accumulated amortization	(3,771)		(3,590)
Other intangible assets, net	4,911		5,024
Accounts payable and other current liabilities	1,087		1,119
Long-term debt and finance lease obligations	8,189		$ 8,280
Total finance lease liabilities	138
Cash paid for amounts included in the measurement of lease liabilities
Operating cash flows used in finance leases	(7)
Operating cash flows used in operating leases	(106)
Financing cash flows used in finance leases	(44)
Right-of-use assets obtained in exchange for new finance lease liabilities	17
Right-of-use assets obtained in exchange for new operating lease liabilities	$ 41
Weighted-average remaining lease term--finance leases	4 years
Weighted-average remaining lease term--operating leases	8 years
Weighted-average discount rate--finance leases	6.30%
Weighted-average discount rate--operating leases	4.50%
Finance Leases
Finance leases
Property, plant and equipment, gross	$ 372
Accumulated depreciation	(203)
Property, plant and equipment, net	169
Other intangible assets, gross	23
Accumulated amortization	(12)
Other intangible assets, net	11
Accounts payable and other current liabilities	53
Long-term debt and finance lease obligations	85
Other Current Liabilities
Operating leases
Total operating lease liabilities	110
Operating Lease Liabilities
Operating leases
Total operating lease liabilities	$ 393