Retirement Plans (Tables)

12 Months Ended

Dec. 31, 2018

Retirement Benefits [Abstract]

Reconciliation of Balances of Pension Benefit Obligation and Fair Value of Plan Assets

A reconciliation of the beginning and ending balances of the pension benefit obligation and fair value of plan assets and the funded status of the plan is as follows (in millions):

	Year Ended December 31,
	2018			2017
Change in pension benefit obligation:
Benefit obligation at beginning of year	$	271.4		$	261.3
Service cost		0.8			1.7
Interest cost		9.3			10.0
Net actuarial (gain) loss		(14.3	)		11.5
Benefits paid		(14.0	)		(13.1	)
Benefit obligation at end of year	$	253.2		$	271.4
Change in plan assets:
Fair value of plan assets at beginning of year	$	219.4		$	207.8
Actual return on plan assets		(15.4	)		24.7
Contributions by the company		30.0			—
Benefits paid		(14.0	)		(13.1	)
Fair value of plan assets at end of year	$	220.0		$	219.4
Funded status of the plan (underfunded)	$	(33.2	)	$	(52.0	)
Amounts recognized in the consolidated balance sheet consist of:
Noncurrent liabilities - accrued benefit liability	$	(33.2	)	$	(52.0	)
Accumulated other comprehensive loss - net actuarial loss		76.0			63.7
Net amount included in retained earnings	$	42.8		$	11.7

Components of Net Periodic Pension Benefit Cost and Other Changes in Plan Assets and Obligations Recognized in Earnings and Other Comprehensive Earnings

The components of the net periodic pension benefit cost for the plan and other changes in plan assets and obligations recognized in earnings and other comprehensive earnings consist of the following (in millions):

	Year Ended December 31,
	2018			2017			2016
Net periodic pension cost:
Service cost	$	0.8		$	1.7		$	1.5
Interest cost on benefit obligation		9.3			10.0			10.8
Expected return on plan assets		(16.0	)		(14.0	)		(14.6	)
Amortization of net loss		4.9			5.0			5.3
Net periodic benefit cost		(1.0	)		2.7			3.0
Other changes in plan assets and obligations recognized in other comprehensive earnings:
Net loss incurred		17.2			0.8			1.4
Amortization of net loss		(4.9	)		(5.0	)		(5.3	)
Total recognized in other comprehensive loss		12.3			(4.2	)		(3.9	)
Total recognized in net periodic pension cost and other comprehensive loss	$	11.3		$	(1.5	)	$	(0.9	)
Estimated amortization for the following year:
Amortization of net loss	$	7.2		$	5.0		$	5.5

Weighted Average Assumptions of Pension Benefit Obligation and Net Periodic Pension Benefit Cost

The following weighted average assumptions were used at December 31 in determining the plan’s pension benefit obligation:

	December 31,
	2018			2017
Discount rate		4.00	%		3.50	%
Weighted average expected long-term rate of return on plan assets		7.00	%		7.00	%

The following weighted average assumptions were used at January 1 in determining the plan’s net periodic pension benefit cost:

	Year Ended December 31,
	2018			2017			2016
Discount rate		3.50	%		4.00	%		4.25	%
Weighted average expected long-term rate of return on plan assets		7.00	%		7.00	%		7.25	%

Schedule of Benefit Payments Expected to be Paid by Plan

The following benefit payments are expected to be paid by the plan (in millions):

2019	$	15.8
2020		16.1
2021		16.3
2022		16.5
2023		16.6
Years 2024 to 2028		82.8

Summary of Plans Weighted Average Asset Allocations

The following is a summary of the plan’s weighted average asset allocations at December 31 by asset category:

	December 31,
Asset Category	2018			2017
Equity securities		57.0	%		61.0	%
Debt securities		36.0	%		32.0	%
Real estate		7.0	%		7.0	%
Total		100.0	%		100.0	%

Summary of Plan's Assets Carried at Fair Value

The following is a summary of the plan’s assets carried at fair value as of December 31 by level within the fair value hierarchy (in millions):

	December 31,
Fair Value Hierarchy	2018		2017
Level 1	$	—	$	—
Level 2		125.1		107.5
Level 3		94.9		111.9
Total fair value	$	220.0	$	219.4

Reconciliation of Beginning and Ending Balances for Level 3 Assets of Plan Measured at Fair Value

The following is a reconciliation of the beginning and ending balances for the Level 3 assets of the plan measured at fair value (in millions):

	Year Ended December 31,
	2018			2017
Fair value at January 1	$	111.9		$	99.7
Settlements		(9.6	)		—
Unrealized (loss) gains		(7.4	)		12.2
Fair value at December 31	$	94.9		$	111.9