Employment Benefit Plans (Tables)

12 Months Ended

Dec. 31, 2019

Retirement Benefits [Abstract]

Schedule of Net Benefit Costs

Components of the net (benefit) cost for the Pension Plans were as follows (in millions):

	Pension Benefits
	Years ended December 31,
	2019			2018			2017
Service cost	$	32		$	46		$	42
Interest cost	81			82			88
Expected return on plan assets	(160		)	(157		)	(149		)
Amortization of net loss	—			1			—
Amortization of prior service credits	(3		)	(1		)	—
Curtailment gain	(117		)	—			—
Settlement loss (gain)	5			(1		)	—
Net (benefit) cost recognized	$	(162	)	$	(30	)	$	(19	)

Schedule of Changes in Projected Benefit Obligations

The following tables show the change in projected benefit obligation for the Pension Plans (in millions):

	Pension Benefits
Change in Benefit Obligation	December 31, 2019			December 31, 2018
Projected benefit obligation at beginning of period	$	2,198		$	2,387
Service cost	32			46
Interest cost	81			82
Actuarial loss (gain)	279			(158		)
Benefits paid	(142		)	(149		)
Curtailments	(117		)	—
Settlements	(36		)	(10		)
Projected benefit obligation at end of period	2,295			2,198
Component representing future salary increases	(44		)	(136		)
Accumulated benefit obligation at end of period	$	2,251		$	2,062

Schedule of Changes in Plan Assets

The following tables show the change in plan assets of the Pension Plans (in millions):

	Pension Benefits
Change in Plan Assets	December 31, 2019			December 31, 2018
Fair value of plan assets at beginning of period	$	2,336		$	2,669
Actual return (loss) on plan assets	482			(189		)
Employer contributionsa	—			3
Benefits paid	(134		)	(137		)
Settlements	(12		)	(10		)
Fair value of plan assets at measurement date	$	2,672		$	2,336

^a  Employer contributions were classified as Other, Net under Operating Activities in the Company’s Consolidated Statements of Cash Flows.

Schedule of Net Funded Status

The following table shows the funded status of the Pension Plans, defined as plan assets less the projected benefit obligation (in millions):

	Pension Benefits
	December 31, 2019		December 31, 2018
Funded status (plan assets less projected benefit obligations)	$	377	$	138

Defined Benefit Plan, Plan with Accumulated Benefit Obligation in Excess of Plan Assets

The following table shows the projected benefit obligation, accumulated benefit obligation, and fair value of plan assets for the plans (in millions):

	December 31, 2019		December 31, 2018
Projected benefit obligation	$	113	$	138
Accumulated benefit obligation	$	113	$	138
Fair value of plan assets	$	25	$	36

Schedule of Amounts Recognized in Other Comprehensive Income (Loss)

The following tables show the pre-tax change in AOCI attributable to the components of the net cost and the change in benefit obligation (in millions):

	Pension Benefits
	Years ended December 31,
Change in AOCI	2019			2018			2017
Beginning balance	$	182		$	371		$	207
Amortization of net loss	—			1			—
Amortization of prior service credits	(3		)	(1		)	—
Actuarial gain (loss)	44			(188		)	164
Settlements	5			(1		)	—
Ending balance	$	228		$	182		$	371

Schedule of Accumulated Other Comprehensive Income (Loss)

Pre-tax amounts currently recognized in AOCI consist of the following (in millions):

	Pension Benefits
	Years ended December 31,
	2019		2018
Net gain (loss)	$	227	$	183
Prior service credits	—		3
Settlements	1		(4		)
Pre-tax amount recognized in AOCI at December 31,	$	228	$	182

Defined Benefit Plan, Assumptions

The assumptions used in accounting for the Pension Plans were as follows:

	Pension Benefits
	Years ended December 31,
Assumptions Used to Determine Net Cost	2019		2018		2017
Discount rate	4.2	%	3.6	%	4.1	%
Expected long-term rate of return on plan assets	6.7	%	6.6	%	6.6	%
Rate of compensation increase	3.5	%	3.6	%	3.3	%

	Pension Benefits
Assumptions Used to Determine Benefit Obligations	December 31, 2019		December 31, 2018
Discount rate	3.2	%	4.2	%
Rate of compensation increase	3.1	%	3.5	%

Sensitivity analysis of impact on future net benefit cost resulting from hypothetical change in assumptions

The following table is an estimate of the impact on future net benefit cost that could result from hypothetical changes to the most sensitive assumptions, the discount rate and expected rate of return on plan assets:

Sensitivity Analysis
	Change in 2020 Net Benefit Cost
Hypothetical Discount Rate Change	Pension
50 basis point decrease	$	5	million	decrease
50 basis point increase	$	2	million	increase
Hypothetical Expected Rate of Return on Plan Assets Change	Pension
50 basis point decrease	$	13	million	increase
50 basis point increase	$	13	million	decrease

Schedule of Allocation of Plan Assets

The following table summarizes the investments of the funded pension plans as of December 31, 2019, based on the inputs used to value them (in millions):

	Total as of
Asset Category	December 31, 2019		Level 1 Inputs a		Level 2 Inputs a		Level 3 Inputs a
Cash and equivalents	$	32	$	2	$	30	$	—
Equity securitiesb	2,518		2,518		—		—
Government obligations	111		111		—		—
Other fixed maturity securities	11		—		11		—
Investment funds and other	—		—		—		—
Totalc	$	2,672	$	2,631	$	41	$	—

^a See Note 2 to the Consolidated Financial Statements under the heading “Fair Value Measurements” for a definition of each of these levels of inputs.

^b As of December 31, 2019, three equity securities each exceeded 10 percent of total plan assets. These investments represent approximately 58 percent of total plan assets.

^c Excludes less than $1 million accrued for dividend and interest receivable.

Comparative Prior Year Information

The following table summarizes the investments of the funded pension plans as of December 31, 2018, based on the inputs used to value them (in millions):

	Total as of
Asset Category	December 31, 2018		Level 1 Inputs a		Level 2 Inputs a		Level 3 Inputs a
Cash and equivalents	$	21	$	1	$	20	$	—
Equity securitiesb	1,895		1,895		—		—
Government obligations	403		403		—		—
Other fixed maturity securities	14		—		14		—
Investment funds and other	3		3		—		—
Total c	$	2,336	$	2,302	$	34	$	—

^a See Note 2 to the Consolidated Financial Statements under the heading “Fair Value Measurements” for a definition of each of these levels of inputs.

^b As of December 31, 2018, three equity securities each exceeded 10 percent of total plan assets.  These investments represented approximately 51 percent of total plan assets.

^c Excludes less than $1 million accrued for dividend and interest receivable.

Schedule of Expected Benefit Payments

The following table shows expected benefit payments from the Pension Plans for the next five fiscal years and the aggregate five years thereafter (in millions):

Fiscal year	Expected Pension Plan Benefit Paymentsa
2020	$	156
2021	$	144
2022	$	140
2023	$	136
2024	$	132
2025-2029	$	620

^a Primarily consists of the BNSF Retirement Plan payments, which are made from the plan trust and do not represent an immediate cash outflow to the Company.