Income Taxes - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Dec. 31, 2014	Jan. 02, 2014
Income Tax Disclosure [Abstract]
Deferred tax assets, gross	$ 136.4us-gaap_DeferredTaxAssetsGross	$ 138.3us-gaap_DeferredTaxAssetsGross
Valuation allowance	114.1	114.2
Estimated recoverable deferred income tax assets	22.2us-gaap_DeferredTaxAssetsNet	24.1us-gaap_DeferredTaxAssetsNet
Percentage of probability of deferred income tax realized in future	50.00%
Valuation allowance, methodologies and assumptions	"more likely than not" (greater than a 50% probability)
Federal income tax at statutory rate	35.00%
Approximate Federal net operating losses ("NOLs") available to offset future taxable income	308.6us-gaap_OperatingLossCarryforwards
Limited net operating losses rate under "IRC Section 382"			44.3
Allowable net operating losses utilize per year under "IRC Section 382"			$ 6.1

Estimated operating loss to be utilized per year as per internal revenue code.

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Operating loss carryforwards limit amount under internal revenue code.

+ References

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- Definition

Percentage of probability of deferred income tax realized in future.

+ References

No definition available.

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- Definition

Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32537-109319

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Deferred Tax Asset

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Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

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- Definition

Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 13

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-Name Accounting Standards Codification

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- Definition

Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (a)

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Describes the methodologies and assumptions on which the valuation allowance is based for deferred tax assets for which it is more likely than not that all or a portion of the deferred tax asset will not be realized.

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