Pension and Postretirement Health Care (Tables)

6 Months Ended

Jun. 30, 2017

Retirement Benefits [Abstract]

Net Periodic Pension Expense (Benefit)

The following tables set forth the net periodic pension and postretirement benefit expense for Northern Trust’s U.S. and non-U.S. pension plans, supplemental pension plan, and postretirement health care plan for the three and six months ended June 30, 2017 and 2016.

Table 57: Net Periodic Pension Expense (Benefit)

Net Periodic Pension Expense U.S. Plan	Three Months Ended June 30,						Six Months Ended June 30,
(In Millions)	2017			2016			2017			2016
Service Cost	$	9.6		$	9.4		$	19.2		$	18.7
Interest Cost	11.5			11.4			23.0			22.9
Expected Return on Plan Assets	(23.5		)	(23.6		)	(47.0		)	(47.2		)
Amortization
Net Actuarial Loss	4.8			4.7			9.6			9.4
Prior Service Cost	(0.1		)	(0.1		)	(0.2		)	(0.2		)
Net Periodic Pension Expense	$	2.3		$	1.8		$	4.6		$	3.6

Net Periodic Pension Expense Non-U.S. Plans	Three Months Ended June 30,						Six Months Ended June 30,
(In Millions)	2017			2016			2017			2016
Interest Cost	$	1.0		$	1.2		$	1.9		$	2.5
Expected Return on Plan Assets	(1.1		)	(1.2		)	(2.2		)	(2.5		)
Settlement Expense	0.2			—			0.2			—
Net Actuarial Loss Amortization	0.3			0.3			0.6			0.6
Net Periodic Pension Expense	$	0.4		$	0.3		$	0.5		$	0.6

Net Periodic Pension Expense Supplemental Plan	Three Months Ended June 30,				Six Months Ended June 30,
(In Millions)	2017		2016		2017		2016
Service Cost	$	0.9	$	0.8	$	1.8	$	1.7
Interest Cost	1.3		1.3		2.6		2.6
Amortization
Net Actuarial Loss	1.4		1.4		2.8		2.9
Prior Service Cost	—		0.1		—		0.1
Net Periodic Pension Expense	$	3.6	$	3.6	$	7.2	$	7.3

Net Periodic Postretirement Expense Postretirement Health Care Plan	Three Months Ended June 30,				Six Months Ended June 30,
(In Millions)	2017		2016		2017		2016
Service Cost	$	—	$	0.1	$	—	$	0.1
Interest Cost	0.4		0.3		0.8		0.7
Amortization
Net Actuarial (Gain)	—		—		—		—
Net Periodic Postretirement Expense	$	0.4	$	0.4	$	0.8	$	0.8