Postretirement Benefit Plans - Other Changes in Plan Assets and Net Periodic Postretirement Cost Recognized in Other Comprehensive Income (Loss) (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
U.S. Pension Plans [Member]
Net periodic postretirement cost
Service cost	$ 4.8	$ 5.6	$ 6.3
Interest cost	12.9	13.4	13.6
Expected return on plan assets	(18.2)	(18.9)	(18.6)
Amortization of net actuarial loss	6.5	3.7	2.4
Amortization of prior service cost	0.9	1.2	1.2
Net periodic postretirement cost	6.9	5.0	4.9
Effect of curtailment / Special termination benefit		2.5
Total net periodic postretirement cost	6.9	7.5	4.9
Other changes in plan assets and benefit obligations recognized in other comprehensive loss
Net actuarial loss (gain)	19.8	51.6	5.6
Prior service cost			1.0
Amortization of net actuarial (loss) gain	(6.5)	(3.7)	(2.4)
Amortization of prior service cost	(0.9)	(2.8)	(1.2)
Total change recognized in other comprehensive loss	12.4	45.1	3.0
Total impact from net periodic postretirement cost and changes in other comprehensive loss	19.3	52.6	7.9
International Pension Plan [Member]
Net periodic postretirement cost
Service cost	1.0	0.9	0.9
Interest cost	2.5	2.5	2.4
Expected return on plan assets	(0.1)	(0.1)	(0.1)
Amortization of net actuarial loss	(0.2)	(0.1)
Net periodic postretirement cost	3.2	3.2	3.2
Effect of curtailment / Special termination benefit			2.0
Total net periodic postretirement cost	3.2	3.2	5.2
Other changes in plan assets and benefit obligations recognized in other comprehensive loss
Net actuarial loss (gain)	14.8	(1.1)	0.1
Prior service cost			0.1
Amortization of net actuarial (loss) gain	0.2	0.1
Foreign currency translation	0.4
Total change recognized in other comprehensive loss	15.4	(1.0)	0.2
Total impact from net periodic postretirement cost and changes in other comprehensive loss	18.6	2.2	5.4
Pension [Member]
Net periodic postretirement cost
Service cost	5.8	6.5	7.2
Interest cost	15.4	15.9	16.0
Expected return on plan assets	(18.3)	(19.0)	(18.7)
Amortization of net actuarial loss	6.3	3.6	2.4
Amortization of prior service cost	0.9	1.2	1.2
Net periodic postretirement cost	10.1	8.2	8.1
Effect of curtailment / Special termination benefit		2.5	2.0
Total net periodic postretirement cost	10.1	10.7	10.1
Other changes in plan assets and benefit obligations recognized in other comprehensive loss
Net actuarial loss (gain)	34.6	50.5	5.7
Prior service cost			1.1
Amortization of net actuarial (loss) gain	(6.3)	(3.6)	(2.4)
Amortization of prior service cost	(0.9)	(2.8)	(1.2)
Foreign currency translation	0.4
Total change recognized in other comprehensive loss	27.8	44.1	3.2
Total impact from net periodic postretirement cost and changes in other comprehensive loss	37.9	54.8	13.3
Others Benefits [Member]
Net periodic postretirement cost
Service cost	2.5	1.8	1.5
Interest cost	9.5	9.5	9.3
Expected return on plan assets	(0.5)	(0.6)	(0.8)
Amortization of net actuarial loss	4.6	2.6	1.4
Amortization of prior service cost	(0.1)	(0.1)	(0.1)
Total net periodic postretirement cost	16.0	13.2	11.3
Other changes in plan assets and benefit obligations recognized in other comprehensive loss
Net actuarial loss (gain)	22.1	14.5	2.0
Prior service cost	(3.1)
Amortization of net actuarial (loss) gain	(4.6)	(2.6)	(1.4)
Amortization of prior service cost	0.1	0.1	0.1
Total change recognized in other comprehensive loss	14.5	12.0	0.7
Total impact from net periodic postretirement cost and changes in other comprehensive loss	$ 30.5	$ 25.2	$ 12.0