Property and Equipment, Net (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Property, Plant and Equipment [Line Items]
Leasehold improvements	$ 24,442	$ 24,020
Equipment and furniture	21,942	19,876
Construction in progress	46,549
Property, Plant and Equipment, Gross, Total	92,933	43,896
Less accumulated depreciation and amortization	(37,875)	(36,215)
Property and equipment, net	$ 55,058	$ 7,681

Gross amount, at the balance sheet date, of equipment and furniture.

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Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Amount of structure or a modification to a structure under construction. Includes recently completed structures or modifications to structures that have not been placed into service.

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Amount before accumulated depreciation of additions or improvements to assets held under a lease arrangement.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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