Stockholders' Equity (Deficit) Accumulated Other Comprehensive Income and Redeemable Noncontrolling Interest - Stockholders' Equity (Parenthetical) (Detail) (USD $) In Millions, unless otherwise specified	9 Months Ended
	Sep. 30, 2014
Accumulated Other Comprehensive Income (Loss) [Line Items]
Net of tax provision	$ 2.8
Net of tax benefit	3.2
Benefit Plan Liabilities [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Net of tax provision	2.8
Unrealized Gain (Loss) on Available-For-Sale Investments [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Net of tax benefit	$ 3.2