Pension Plans, Retirement Benefits and Savings Plans (tables)

3 Months Ended

Mar. 31, 2017

Pension Plans, Retirement Benefits and Savings Plans disclosure

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]

	Pension Plans						Postretirement Benefit Plans
(for the three months ended March 31, in millions)	2017			2016			2017			2016
Net Periodic Benefit Cost:
Service cost	$	30		$	29		$	—		$	—
Non-service cost:
Interest cost on benefit obligation	31			30			2			2
Expected return on plan assets	(60		)	(57		)	—			—
Amortization of unrecognized:
Prior service benefit	—			—			(1		)	(1		)
Net actuarial loss	18			17			—			—
Total non-service cost	(11		)	(10		)	1			1
Net periodic benefit cost	$	19		$	19		$	1		$	1

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

	Pension Plans						Postretirement Benefit Plans
(for the three months ended March 31, in millions)	2017			2016			2017		2016
Service Cost:
Claims and claim adjustment expenses	$	12		$	12		$	—	$	—
General and administrative expenses	18			17			—		—
Total service cost	30			29			—		—
Non-Service Cost:
Claims and claim adjustment expenses	(4		)	(4		)	—		—
General and administrative expenses	(7		)	(6		)	1		1
Total non-service cost	(11		)	(10		)	1		1
Net periodic benefit cost	$	19		$	19		$	1	$	1