Condensed Consolidated Statements of Operations - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Income Statement [Abstract]
Net Sales	$ 1,599.1	$ 1,505.9
Cost of Sales	1,278.3	1,239.8
Selling, General and Administrative	135.6	124.7
Other Expense, Net	6.5	1.2
Business Combinations and Shutdown and Other Special Charges, Net	18.7	6.2
Income from Operations	160.0	134.0
Nonoperating Pension and Postretirement Benefit Expense	(151.6)	(0.1)
Interest Expense, Net	(33.7)	(35.0)
(Loss) Income before Income Taxes and Equity Income of Unconsolidated Entity	(25.3)	98.9
Income Tax Benefit (Expense)	5.4	(21.0)
(Loss) Income before Equity Income of Unconsolidated Entity	(19.9)	77.9
Equity Income of Unconsolidated Entity	0.1	0.2
Net (Loss) Income	(19.8)	78.1
Net Loss (Income) Attributable to Noncontrolling Interest	7.1	(20.2)
Net (Loss) Income Attributable to Graphic Packaging Holding Company	$ (12.7)	$ 57.9
Net Income Per Share Attributable to Graphic Packaging Holding Company — Basic (in dollars per share)	$ (0.04)	$ 0.19
Net Income Per Share Attributable to Graphic Packaging Holding Company — Diluted (in dollars per share)	(0.04)	0.19
Cash Dividends Declared Per Share (in dollars per share)	$ 0.075	$ 0.075