Long-Term Incentive Employee Compensation - Number of Outstanding Equity Settled RSUs, Cash Settled RSUs and RSAs (Detail) In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Equity settled RSUs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity and Cash settled shares	1.0	0.9	0.8
Cash settled RSUs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity and Cash settled shares	0.1	0.1	0.1
PSUs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity and Cash settled shares	0.2	0	0
RSAs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity and Cash settled shares	0	0.2	0.5