Guarantor Financial Information - Condensed Consolidated Balance Sheet (Unaudited) (Detail) - USD ($) $ in Millions	Sep. 30, 2019	Jun. 30, 2019	Jan. 01, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Dec. 31, 2017
Current assets
Cash and cash equivalents	$ 389			$ 524
Trade and other receivables, net	1,146			1,118
Prepaid expenses and other current assets	412			361
Total current assets	1,947			2,003
Non-current assets
Property, plant and equipment, net	423			468
Operating lease right-of-use asset	425		$ 500
Goodwill	5,973			6,987
Other intangible assets, net	4,911			5,024
Deferred tax assets	322			333
Other non-current assets	342			364
Total assets	14,343			15,179
Current liabilities
Accounts payable and other current liabilities	1,087			1,119
Deferred revenues	316			355
Income tax liabilities	74			76
Current portion of long-term debt, finance lease obligations and short-term borrowings	298			107
Total current liabilities	1,775			1,657
Non-current liabilities
Long-term debt and finance lease obligations	8,189			8,280
Operating lease liabilities	393
Deferred tax liabilities	1,068			1,108
Other non-current liabilities	565			1,091
Total liabilities	11,990			12,136
Total stockholders’ equity	2,155			2,847
Noncontrolling interests	198			196
Total equity	2,353	$ 2,988		3,043	$ 4,215	$ 4,245	$ 4,443
Total liabilities and equity	14,343			15,179
Parent
Current assets
Cash and cash equivalents	2			3
Prepaid expenses and other current assets	3
Intercompany receivables	4			3
Total current assets	9			6
Non-current assets
Deferred tax assets	1			1
Equity investment in subsidiaries	2,120			2,815
Intercompany loans	25			25
Total assets	2,155			2,847
Non-current liabilities
Total stockholders’ equity	2,155			2,847
Total equity	2,155			2,847
Total liabilities and equity	2,155			2,847
Issuers
Current assets
Trade and other receivables, net				1
Prepaid expenses and other current assets				3
Intercompany receivables	1,632			1,310
Total current assets	1,632			1,314
Non-current assets
Other non-current assets				19
Equity investment in subsidiaries	1,285			1,232
Intercompany loans	8,838			8,822
Total assets	11,755			11,387
Current liabilities
Accounts payable and other current liabilities	102			62
Current portion of long-term debt, finance lease obligations and short-term borrowings	55			54
Intercompany payables	5
Total current liabilities	162			116
Non-current liabilities
Long-term debt and finance lease obligations	8,104			8,170
Deferred tax liabilities	71			71
Other non-current liabilities	30			3
Total liabilities	8,367			8,360
Total stockholders’ equity	3,388			3,027
Total equity	3,388			3,027
Total liabilities and equity	11,755			11,387
Guarantor
Current assets
Cash and cash equivalents	19			79
Trade and other receivables, net	440			377
Prepaid expenses and other current assets	279			234
Intercompany receivables	283			399
Total current assets	1,021			1,089
Non-current assets
Property, plant and equipment, net	266			303
Operating lease right-of-use asset	210
Goodwill	5,102			5,531
Other intangible assets, net	4,410			4,545
Other non-current assets	272			273
Equity investment in subsidiaries	3,077			1,936
Intercompany loans	873			2,220
Total assets	15,231			15,897
Current liabilities
Accounts payable and other current liabilities	455			541
Deferred revenues	190			225
Income tax liabilities	28			20
Current portion of long-term debt, finance lease obligations and short-term borrowings	236			46
Intercompany payables	1,693			1,408
Total current liabilities	2,602			2,240
Non-current liabilities
Long-term debt and finance lease obligations	74			95
Operating lease liabilities	228
Deferred tax liabilities	927			956
Intercompany loans	8,965			8,952
Other non-current liabilities	315			839
Total liabilities	13,111			13,082
Total stockholders’ equity	2,120			2,815
Total equity	2,120			2,815
Total liabilities and equity	15,231			15,897
Non-Guarantor
Current assets
Cash and cash equivalents	368			442
Trade and other receivables, net	706			740
Prepaid expenses and other current assets	130			124
Intercompany receivables	57			94
Total current assets	1,261			1,400
Non-current assets
Property, plant and equipment, net	157			165
Operating lease right-of-use asset	215
Goodwill	871			1,456
Other intangible assets, net	501			479
Deferred tax assets	321			332
Other non-current assets	70			72
Intercompany loans	102			105
Total assets	3,498			4,009
Current liabilities
Accounts payable and other current liabilities	530			516
Deferred revenues	126			130
Income tax liabilities	46			56
Current portion of long-term debt, finance lease obligations and short-term borrowings	7			7
Intercompany payables	278			398
Total current liabilities	987			1,107
Non-current liabilities
Long-term debt and finance lease obligations	11			15
Operating lease liabilities	165
Deferred tax liabilities	70			81
Intercompany loans	873			2,220
Other non-current liabilities	220			249
Total liabilities	2,326			3,672
Total stockholders’ equity	974			141
Noncontrolling interests	198			196
Total equity	1,172			337
Total liabilities and equity	3,498			4,009
Consolidation Eliminations
Current assets
Intercompany receivables	(1,976)			(1,806)
Total current assets	(1,976)			(1,806)
Non-current assets
Equity investment in subsidiaries	(6,482)			(5,983)
Intercompany loans	(9,838)			(11,172)
Total assets	(18,296)			(18,961)
Current liabilities
Intercompany payables	(1,976)			(1,806)
Total current liabilities	(1,976)			(1,806)
Non-current liabilities
Intercompany loans	(9,838)			(11,172)
Total liabilities	(11,814)			(12,978)
Total stockholders’ equity	(6,482)			(5,983)
Total equity	(6,482)			(5,983)
Total liabilities and equity	$ (18,296)			$ (18,961)