A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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- Definition

Amount after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

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- Definition

Amount after tax, before reclassification adjustments, of other comprehensive income (loss), attributable to parent.

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- Definition

Amount after tax of other comprehensive income (loss) attributable to parent entity.

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Amount after tax of reclassification adjustments of other comprehensive income (loss) attributable to parent.

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- Definition

Amount of stockholders' equity (deficit), net of receivables from officers, directors, owners, and affiliates of the entity, attributable to both the parent and noncontrolling interests. Amount excludes temporary equity. Alternate caption for the concept is permanent equity.

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Amount of stockholders' equity including the portion attributable to noncontrolling interests, after the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

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Comprehensive Income (Detail) - USD ($) $ in Millions	12 Months Ended
Comprehensive Income (Detail) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Jan. 01, 2019	Jan. 01, 2018	Jan. 01, 2017
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at beginning of year	$ 54,710	$ 44,687
Other comprehensive income	(675)	(855)	$ 1,400
Amounts reclassified to net income	(697)	(64)	(1,414)
Other comprehensive loss attributable to Verizon	(1,372)	(919)	(14)
Balance at end of year	62,835	54,710	44,687
Foreign currency translation adjustments
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at beginning of year	(600)	(468)	(713)
Opening balance sheet adjustment (Note 1)					$ (15)
Adjusted opening balance					(483)
Other comprehensive income	16	(117)	245
Amounts reclassified to net income	0	0	0
Other comprehensive loss attributable to Verizon	16	(117)	245
Balance at end of year	(584)	(600)	(468)
Unrealized gains (losses) on cash flow hedges
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at beginning of year	(80)	(111)	(80)
Opening balance sheet adjustment (Note 1)					(24)
Adjusted opening balance					(135)
Other comprehensive income	(699)	(574)	818
Amounts reclassified to net income	(37)	629	(849)
Other comprehensive loss attributable to Verizon	(736)	55	(31)
Balance at end of year	(816)	(80)	(111)
Unrealized gains (losses) on marketable securities
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at beginning of year	20	32	46
Opening balance sheet adjustment (Note 1)					(13)
Adjusted opening balance					19
Other comprehensive income	8	0	10
Amounts reclassified to net income	(1)	1	(24)
Other comprehensive loss attributable to Verizon	7	1	(14)
Balance at end of year	27	20	32
Defined benefit pension and postretirement plans
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at beginning of year	3,030	3,206	3,420
Opening balance sheet adjustment (Note 1)					682
Adjusted opening balance					3,888
Other comprehensive income	0	(164)	327
Amounts reclassified to net income	(659)	(694)	(541)
Other comprehensive loss attributable to Verizon	(659)	(858)	(214)
Balance at end of year	2,371	3,030	3,206
Accumulated Other Comprehensive Income
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at beginning of year	2,370	2,659	2,673
Opening balance sheet adjustment (Note 1)				$ 0	630	$ 0
Adjusted opening balance				$ 2,370	$ 3,289	$ 2,673
Balance at end of year	$ 998	$ 2,370	$ 2,659