Accumulated Other Comprehensive Income

3 Months Ended

Mar. 31, 2019

Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]

Accumulated Other Comprehensive Income

Accumulated Other Comprehensive Income

Other comprehensive income refers to revenues, expenses, gains and losses that under generally accepted accounting principles are included in accumulated other comprehensive income, a component of equity within the Consolidated Balance Sheets, rather than net income on the Consolidated Statements of Income. Under existing accounting standards, other comprehensive income may include, among other things, unrecognized gains and losses and prior service credit related to pension and other postretirement benefit plans.

The following table provides the components of accumulated other comprehensive income (loss) (AOCI) by component (in millions):

	Pension and Retiree Health and Welfare Benefit Items			Equity Method Investments			Accumulated Other Comprehensive Income (Loss)
Balance at December 31, 2018	$	133		$	(3	)	$	130
Other comprehensive income (loss), net before reclassifications	66			(1		)	65
Amounts reclassified from AOCI:
Amortization of net gaina	(1		)	—			(1		)
Amortization of prior service creditsa	(3		)	—			(3		)
Tax expense (benefit)	1			—			1
Balance at March 31, 2019	$	196		$	(4	)	$	192
Balance at December 31, 2017	$	234		$	(3	)	$	231
Other comprehensive income (loss), net before reclassifications	—			1			1
Amounts reclassified from AOCI:
Reclassification due to ASU 2016-01 adoption	—			(1		)	(1		)
Reclassification due to ASU 2018-02 adoption	26			—			26
Balance at March 31, 2018	$	260		$	(3	)	$	257

^a This accumulated other comprehensive income component is included in the computation of net periodic pension and retiree health and welfare cost (see Note 7 for additional details).