Discontinued Operations - Schedule of Financial Results of Discontinued Operations (Parenthetical) (Detail) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Loss on debt extinguishment	$ 10.8	$ 20.1	$ 96.1
Donnelley Financial Solutions And L S C Communications | Discontinued Operations Spinoff
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Spinoff transaction costs			81.2	$ 13.6
Loss on debt extinguishment			96.1
Donnelley Financial Solutions And L S C Communications | Discontinued Operations Spinoff | Corporate Level Debt
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Interest expense			55.9	$ 73.3
Loss on debt extinguishment			$ 96.1