Income Taxes - Reconciliation of Expected Income Tax (Benefit) Expense Computed Using Federal Statutory Income Tax Rate (Detail)	12 Months Ended
Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Income Tax Disclosure [Abstract]
Income tax benefit computed at federal statutory tax rate	35.00%	35.00%	35.00%
State taxes, net of federal benefit	4.02%	7.07%	3.95%
Change in valuation allowance	(38.02%)	(28.08%)	(74.29%)
General business credits and other credits	0.52%	0.12%	(2.36%)
Permanent differences	(1.75%)	(0.63%)	(0.60%)
Interest and penalties	(1.19%)	(1.95%)	(1.72%)
Other	(0.07%)	0.79%	(3.66%)
Total	(1.49%)	12.32%	(43.68%)

Effective income tax rate reconciliation general business credits and other credits.

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Effective income tax rate reconciliation penalties and interest.

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Effective income tax rate reconciliation permanent differences.

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

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to changes in the valuation allowance for deferred tax assets.

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Percentage of the difference, between reported income tax expense (benefit) and the expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations, that is attributable to tax exempt income, equity in earnings (loss) of an unconsolidated subsidiary, minority interest income (expense), tax holiday, disposition of a business, disposition of an asset, repatriation of foreign earnings, repatriation of foreign earnings jobs creation act of 2004, change in enacted tax rate, prior year income taxes, change in deferred tax asset valuation allowance, and other adjustments.

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations applicable to state and local income tax expense (benefit), net of federal tax expense (benefit).

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