Income Taxes (Narrative) (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Income Tax [Line Items]
Company's effective tax rate	32.70%	31.90%
Federal statutory income tax rate	35.00%	35.00%
Increase in gross unrecognized tax benefits	$ 0.1
Recognized interest expense related to unrecognized tax benefits	0.3
Interest and penalty related to unrecognized tax benefits recorded	5.0		4.7
Reasonable possible decrease in unrecognized tax benefits during the next twelve months	$ (4.6)

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 10

-Section 50

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-Number 210

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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The amount of the unrecognized tax benefit of a position taken for which it is reasonably possible that the total amount thereof will significantly increase or decrease within twelve months of the balance sheet date.

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Amount of expense for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

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Amount of interest expense accrued for an underpayment of income taxes.

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Amount of interest expense for an underpayment of income taxes.

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