Pension Plans, Retirement Benefits and Savings Plans (Tables)

9 Months Ended

Sep. 30, 2018

Retirement Benefits [Abstract]

Summary of the components of net periodic benefit cost for the Company's pension and postretirement benefit plans recognized in the consolidated statement of income [Table Text Block]

The following table summarizes the components of net periodic benefit cost for the Company’s pension and postretirement benefit plans recognized in the consolidated statement of income for the three months ended September 30, 2018 and 2017.

	Pension Plans						Postretirement Benefit Plans
(for the three months ended September 30, in millions)	2018			2017			2018			2017
Net Periodic Benefit Cost:
Service cost	$	33		$	30		$	—		$	—
Non-service cost:
Interest cost on benefit obligation	32			35			1			2
Expected return on plan assets	(66		)	(60		)	—			—
Amortization of unrecognized:
Prior service benefit	—			(1		)	(1		)	(1		)
Net actuarial loss	22			29			—			—
Total non-service cost (benefit)	(12		)	3			—			1
Net periodic benefit cost	$	21		$	33		$	—		$	1

The following table summarizes the components of net periodic benefit cost for the Company’s pension and postretirement benefit plans recognized in the consolidated statement of income for the nine months ended September 30, 2018 and 2017.

	Pension Plans						Postretirement Benefit Plans
(for the nine months ended September 30, in millions)	2018			2017			2018			2017
Net Periodic Benefit Cost:
Service cost	$	99		$	90		$	—		$	—
Non-service cost:
Interest cost on benefit obligation	95			96			5			5
Expected return on plan assets	(198		)	(180		)	—			—
Amortization of unrecognized:
Prior service benefit	(1		)	(1		)	(3		)	(3		)
Net actuarial loss	68			66			—			—
Total non-service cost (benefit)	(36		)	(19		)	2			2
Net periodic benefit cost	$	63		$	71		$	2		$	2

Consolidated statement of income line items impacted by service costs and non-service benefit costs [Table Text Block]

The following table indicates the line items in which the respective service costs and non-service benefit costs are presented in the consolidated statement of income for the nine months ended September 30, 2018 and 2017.

	Pension Plans						Postretirement Benefit Plans
(for the nine months ended September 30, in millions)	2018			2017			2018		2017
Service Cost:
Claims and claim adjustment expenses	$	40		$	37		$	—	$	—
General and administrative expenses	59			53			—		—
Total service cost	99			90			—		—
Non-Service Cost:
Claims and claim adjustment expenses	(14		)	(8		)	1		1
General and administrative expenses	(22		)	(11		)	1		1
Total non-service cost (benefit)	(36		)	(19		)	2		2
Net periodic benefit cost	$	63		$	71		$	2	$	2

The following table indicates the line items in which the respective service costs and non-service benefit costs are presented in the consolidated statement of income for the three months ended September 30, 2018 and 2017.

	Pension Plans					Postretirement Benefit Plans
(for the three months ended September 30, in millions)	2018			2017		2018		2017
Service Cost:
Claims and claim adjustment expenses	$	13		$	13	$	—	$	—
General and administrative expenses	20			17		—		—
Total service cost	33			30		—		—
Non-Service Cost:
Claims and claim adjustment expenses	(4		)	1		—		1
General and administrative expenses	(8		)	2		—		—
Total non-service cost (benefit)	(12		)	3		—		1
Net periodic benefit cost	$	21		$	33	$	—	$	1