Comprehensive Income - Schedule of Changes in Accumulated Other Comprehensive Loss (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Accumulated Other Comprehensive Income Loss [Line Items]
Balance	$ 696.6	$ 620.4	$ 653.7
Other comprehensive (loss) income	92.2	(20.8)	(286.0)
Balance	(92.2)	696.6	620.4
Changes in the Fair Value of Derivatives
Accumulated Other Comprehensive Income Loss [Line Items]
Balance		(0.1)	(0.2)
Other comprehensive income (loss) before reclassifications		0.0	0.0
Amounts reclassified from accumulated other comprehensive loss		0.1	0.1
Amounts reclassified from cumulative translation adjustment		0.0
Amounts reclassified due to disposition of an operating entity	0.0
Other comprehensive (loss) income		0.1	0.1
Balance			(0.1)
Changes in the Fair Value of Available-for-Sale Securities
Accumulated Other Comprehensive Income Loss [Line Items]
Other comprehensive income (loss) before reclassifications	119.3
Other comprehensive (loss) income	119.3
Balance	119.3
Pension and Other Postretirement Benefits Plan Cost
Accumulated Other Comprehensive Income Loss [Line Items]
Balance	(727.5)	(762.3)	(521.4)
Other comprehensive income (loss) before reclassifications	(42.7)	22.1	(303.4)
Amounts reclassified from accumulated other comprehensive loss	52.7	8.9	62.5
Amounts reclassified from cumulative translation adjustment		3.8
Amounts reclassified due to disposition of an operating entity	1.2
Other comprehensive (loss) income	11.2	34.8	(240.9)
Distribution to Donnelley Financial and LSC	556.8
Balance	(159.5)	(727.5)	(762.3)
Translation Adjustments
Accumulated Other Comprehensive Income Loss [Line Items]
Balance	(65.7)	(11.2)	33.5
Other comprehensive income (loss) before reclassifications	(37.1)	(67.6)	(34.7)
Amounts reclassified from accumulated other comprehensive loss	0.0	0.0	(10.0)
Amounts reclassified from cumulative translation adjustment		13.1
Amounts reclassified due to disposition of an operating entity	(0.7)
Other comprehensive (loss) income	(37.8)	(54.5)	(44.7)
Distribution to Donnelley Financial and LSC	88.0
Balance	(15.5)	(65.7)	(11.2)
AOCI Attributable to Parent
Accumulated Other Comprehensive Income Loss [Line Items]
Balance	(793.2)	(773.6)	(488.1)
Other comprehensive income (loss) before reclassifications	39.5	(45.5)	(338.1)
Amounts reclassified from accumulated other comprehensive loss	52.7	9.0	52.6
Amounts reclassified from cumulative translation adjustment		16.9
Amounts reclassified due to disposition of an operating entity	0.5
Other comprehensive (loss) income	92.7	(19.6)	(285.5)
Distribution to Donnelley Financial and LSC	644.8
Balance	$ (55.7)	$ (793.2)	$ (773.6)