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.

+ References

No definition available.

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- Definition

Amount after tax and reclassification adjustments of other comprehensive income (loss).

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- Definition

Amount of tax expense (benefit) allocated to other comprehensive income (loss).

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- Definition

Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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Equity - Accumulated Other Comprehensive Gain (Loss) (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Jan. 01, 2020	Jan. 01, 2019
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Period Start	$ 15,237.0
Adoption of new accounting standards			$ (1.0)	$ (1.0)
Other comprehensive income (loss), net of tax	(21.0)	$ (27.0)
Period End	15,326.0
Other comprehensive income (loss), taxes	10.2	8.2
Accumulated Other Comprehensive Loss
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Period Start	(95.0)	(72.0)
Adoption of new accounting standards				(12.0)
Other comprehensive income (loss), net of tax	(21.0)	(27.0)
Period End	(116.0)	(111.0)
Gain on revaluation of defined benefit plans net of tax expense
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Period Start	(12.0)	(11.0)
Adoption of new accounting standards				(2.0)
Other comprehensive income (loss), net of tax	0.0	0.0
Period End	(12.0)	(13.0)
Other comprehensive income (loss), taxes		0.2
Loss on nonqualified pension plans
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Period Start	(7.0)	(6.0)
Adoption of new accounting standards				0.0
Other comprehensive income (loss), net of tax	0.0
Period End	(7.0)	(6.0)
Unrealized gain during period on derivatives qualifying as cash flow hedges, net of income tax expense
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Period Start	(13.0)	9.0
Other comprehensive income (loss), net of tax	(23.0)	(29.0)
Period End	(36.0)	(20.0)
Other comprehensive income (loss), taxes	8.5	10.9
Reclassification to net income of (gains) losses on cash flow hedges, net of income tax (benefit) expense
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Period Start	(63.0)	(64.0)
Adoption of new accounting standards				(10.0)
Other comprehensive income (loss), net of tax	2.0	2.0
Period End	(61.0)	(72.0)
Other comprehensive income (loss), taxes	(0.3)	(0.7)
Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Period Start	(76.0)	(55.0)
Adoption of new accounting standards				$ (10.0)
Other comprehensive income (loss), net of tax	(21.0)	(27.0)
Period End	$ (97.0)	$ (92.0)