Consolidated Statements of Cash Flows - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2017		Dec. 31, 2016		Dec. 31, 2015
Cash provided by (used in) operating activities:
Net income (loss)		$ 145.2		$ 44.4		$ 84.3
Adjustments to reconcile net income to cash provided by operating activities:
Depreciation and amortization		40.4		38.8		34.6
Deferred income taxes		(25.7)		(7.9)		8.3
Disposal/impairment of assets		2.2		1.5		3.9
Restructuring and other (income) charges, net		3.7		41.2		(7.5)
Share-based compensation		10.1		4.7		0.0
Pension and other postretirement benefit costs		1.3		0.7		0.0
Other non-cash items		7.3		4.8		0.8
Changes in operating assets and liabilities:
Accounts receivable, net		(9.5)		5.7		8.5
Inventories, net		(6.6)		(2.2)		(24.1)
Prepaid and other current assets		6.5		(3.9)		(6.7)
Accounts payable		1.7		(1.5)		(22.3)
Accrued expenses		1.6		(1.9)		1.0
Accrued payroll and employee benefit costs		13.4		15.0		(7.8)
Income taxes		(7.3)		4.5		0.8
Pension contribution		(1.4)		(1.0)		0.0
Restructuring and other spending		(5.5)		(8.3)		0.0
Changes in all other operating assets and liabilities, net		(3.1)		(6.7)		(1.6)
Net cash provided by (used in) operating activities		174.3		127.9		72.2
Cash provided by (used in) investing activities:
Capital expenditures		(52.6)		(56.7)		(100.9)
Proceeds from divestiture		0.0		0.0		11.0
Net investment in equity securities		(1.4)		0.0		0.0
Restricted investment		(1.6)		(69.7)		0.0
Other investing activities, net		(3.0)		0.0		0.6
Net cash provided by (used in) investing activities		(58.6)		(126.4)		(89.3)
Cash provided by (used in) financing activities:
Net borrowings under our revolving credit facility		(111.9)		111.9		0.0
Proceeds from long-term borrowings		75.0		300.0		0.0
Payments on long-term borrowings		0.0		0.0		(5.8)
Debt issuance costs		(1.3)		(3.6)		0.0
Borrowings (repayments) of notes payable and other short-term borrowings, net		0.0		(9.4)		7.1
Tax payments related to withholdings on vested restricted stock units		(1.2)		(0.3)		0.0
Proceeds and withholdings from share-based compensation plans, net		0.5		0.0		0.0
Repurchases of common stock under publicly announced plan		(6.6)		0.0		0.0
Noncontrolling interest distributions		(12.3)		(5.4)		(3.4)
Cash distributed to WestRock at Separation		0.0		(448.5)		0.0
Transactions with WestRock, net		0.0		51.9		29.1
Net cash provided by (used in) financing activities		(57.8)		(3.4)		27.0
Increase (decrease) in cash and cash equivalents		57.9		(1.9)		9.9
Effect of exchange rate changes on cash		(0.5)		0.4		2.2
Cash and cash equivalents
Change in cash, cash equivalents and restricted cash		57.4		(1.5)		12.1
Cash, cash equivalents, and restricted cash at beginning of period (1)		30.5	[1]	32.0	[1]	19.9
Cash, cash equivalents, and restricted cash at end of period	[1]	87.9		30.5		32.0
Supplemental cash flow information:
Cash paid for interest, net of capitalized interest		16.0		15.1		6.5
Cash paid for income taxes, net of refunds		61.9		22.4		1.4
Purchases of property, plant and equipment in accounts payable		$ 5.1		$ 3.7		$ 1.3

[1] There was no restricted cash for the periods ended December 31, 2017, 2016 and 2015, respectively.