Consolidated Statements of Cash Flows - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
CASH FLOWS FROM OPERATING ACTIVITIES:
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	$ 294.0	$ 300.2	$ 228.0
Adjustments to Reconcile Net Income to Net Cash (Used in) Provided by Operating Activities:
Depreciation and Amortization	430.6	330.3	299.3
Amortization of Deferred Debt Issuance Costs	4.4	5.1	4.8
Deferred Income Taxes	26.0	(54.0)	76.7
Amount of Postretirement Expense Less Than Funding	(4.7)	(127.1)	(31.3)
Gain on the Sale of Assets, net	(38.6)	(3.7)	0.0
Other, Net	35.3	2.0	25.4
Changes in Operating Assets and Liabilities, Net of Acquisitions (See Note 3)	(1,120.8)	(645.3)	(528.9)
Net Cash (Used in) Provided by Operating Activities	(373.8)	(192.5)	74.0
CASH FLOWS FROM INVESTING ACTIVITIES:
Capital Spending	(378.8)	(240.9)	(278.6)
Packaging Machinery Spending	(16.4)	(19.2)	(16.0)
Acquisition of Businesses, Net of Cash Acquired	(89.4)	(189.4)	(332.7)
Proceeds Received from Sale of Assets, Net of Selling Costs	49.4	7.9	0.0
Beneficial Interest on Sold Receivables	1,476.7	806.1	592.6
Beneficial Interest Obtained in Exchange for Proceeds	(345.5)	(97.4)	(25.2)
Other, Net	(6.9)	1.0	(5.2)
Net Cash Provided by (Used in) Investing Activities	689.1	268.1	(65.1)
CASH FLOWS FROM FINANCING ACTIVITIES:
Repurchase of Common Stock	(119.1)	(62.1)	(164.9)
Payments on Debt	(152.4)	(25.0)	(25.0)
Proceeds from Issuance of Debt	0.0	0.0	300.0
Borrowings under Revolving Credit Facilities	1,876.9	1,202.9	1,200.0
Payments on Revolving Credit Facilities	(1,787.5)	(1,090.8)	(1,235.8)
Debt Issuance Costs	7.9	0.0	5.3
Repurchase of Common Stock Related to Share-Based Payments	(4.3)	(10.2)	(11.3)
Dividends and Distributions Paid to GPIP Partner	(111.0)	(93.4)	(64.4)
Other, Net	(5.4)	8.8	3.6
Net Cash Used In Financing Activities	(310.7)	(69.8)	(3.1)
EFFECT OF EXCHANGE RATE CHANGES ON CASH	(1.5)	2.5	(1.6)
Net Increase in Cash and Cash Equivalents	3.1	8.3	4.2
Cash and Cash Equivalents at Beginning of Year	67.4	59.1	54.9
CASH AND CASH EQUIVALENTS AT END OF YEAR	70.5	67.4	59.1
Non-cash Investing Activities:
Beneficial Interest Obtained in Exchange for Trade Receivables	1,025.7	734.7	523.7
Non-cash Investment in NACP Combination	1,111.2	0.0	0.0
Non-cash Investing Activities	2,136.9	734.7	523.7
Non-cash Financing Activities:
Non-cash Financing of NACP Combination	660.0	0.0	0.0
Non-Cash Financing Activities	$ 660.0	$ 0.0	$ 0.0