Goodwill and Intangible Assets -Goodwill - (Details) $ in Millions	9 Months Ended
	Sep. 30, 2022 USD ($)
Goodwill [Line Items]
Goodwill, Beginning Balance	$ 923.5
Adjustment related to sale of corrugated assets	(0.1)	[1]
Goodwill, Ending Balance	922.4
Advance Packaging Corporation [Member]
Goodwill [Line Items]
Goodwill, Beginning Balance	923.5
Acquisitions	(1.0)	[2]
Goodwill, Ending Balance	$ 1.0

[1] During the three months ended September 30, 2022, a corrugated products facility sold part of its operations, which primarily included existing inventory. As a result, the Company recorded a $0.1 million adjustment to decrease the goodwill balance

[2] During the nine months ended September 30, 2022, the Company recorded a $1.0 million adjustment to decrease the goodwill balance for the Company's December 2021 acquisition of Advance Packaging.