Equity and Accumulated Other Comprehensive Income - Changes in Components of Total equity (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018	Dec. 31, 2017
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance			$ 54,710
Net income attributable to Verizon	$ 5,194	$ 4,924	14,170	$ 13,589
Foreign currency translation adjustments	(10)	10	(53)	(73)
Unrealized gain (loss) on cash flow hedges, net of tax of $59, $(118), $257 and $(243)	(166)	329	(716)	678
Unrealized gain (loss) on marketable securities	2	(1)	10	(5)
Defined benefit pension and postretirement plans	(169)	(342)	(507)	(688)
Other comprehensive loss			$ (1,266)
Shareholder plans (in shares)			3,800
Total comprehensive income	4,994	5,058	$ 13,305	13,886
Ending Balance	$ 60,312	$ 56,087	$ 60,312	$ 56,087
Dividends declared per common share (USD per share)	$ 0.615	$ 0.6025	$ 1.82	$ 1.7825
Common Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance	$ 429	$ 429	$ 429	$ 424
Beginning balance (in shares)	4,291,434	4,291,434	4,291,434	4,242,374
Common shares issued (in shares)			0	49,060
Common shares issued			$ 0	$ 5
Ending Balance (in shares)	4,291,434	4,291,434	4,291,434	4,291,434
Ending Balance	$ 429	$ 429	$ 429	$ 429
Additional Paid In Capital
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance	13,419	13,438	13,437	11,101
Other	(1)	(2)	(19)	2,335
Ending Balance	13,418	13,436	13,418	13,436
Retained Earnings
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance	47,945	41,657	43,542	35,635
Opening balance sheet adjustment					$ 410	$ 2,232
Adjusted Beginning Balance					43,952	37,867
Net income attributable to Verizon	5,194	4,924	14,170	13,589
Dividends declared ($0.6150, $0.6025 per share)	(2,544)	(2,490)	(7,527)	(7,365)
Ending Balance	50,595	44,091	50,595	44,091
Accumulated Other Comprehensive Income
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance	1,447	3,205	2,370	2,659
Opening balance sheet adjustment					0	630
Adjusted Beginning Balance					2,370	3,289
Foreign currency translation adjustments	(10)	10	(53)	(73)
Unrealized gain (loss) on cash flow hedges, net of tax of $59, $(118), $257 and $(243)	(166)	329	(716)	678
Unrealized gain (loss) on marketable securities	2	(1)	10	(5)
Defined benefit pension and postretirement plans	(169)	(342)	(507)	(688)
Other comprehensive loss	(343)	(4)	(1,266)	(88)
Ending Balance	1,104	3,201	1,104	3,201
Treasury Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance	$ (6,823)	$ (6,990)	$ (6,986)	$ (7,139)
Beginning balance (in shares)	155,669	159,498	159,400	162,898
Employee plans (in shares)	20	79	3,746	3,475
Employee plans	$ 1	$ 3	$ 164	$ 152
Shareholder plans (in shares)			5	4
Shareholder plans			$ 0	$ 0
Ending Balance (in shares)	155,649	159,419	155,649	159,419
Ending Balance	$ (6,822)	$ (6,987)	$ (6,822)	$ (6,987)
Deferred Compensation-ESOPs and Other
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance	165	285	353	416
Restricted stock equity grant	32	41	111	132
Amortization	0	(1)	(267)	(223)
Ending Balance	197	325	197	325
Noncontrolling Interests
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance	1,365	1,551	1,565	1,591
Opening balance sheet adjustment					1	44
Adjusted Beginning Balance					$ 1,566	$ 1,635
Total comprehensive income	143	138	401	385
Distributions and other	(117)	(97)	(576)	(428)
Ending Balance	$ 1,391	$ 1,592	$ 1,391	$ 1,592