Fixed Assets (Summary of Fixed Assets) (Details) (USD $) In Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010	Dec. 31, 2010
Fixed Assets
Furniture and equipment	$ 138,457		$ 138,457		$ 116,650
Building and leasehold improvements	54,003		54,003		51,046
Total	192,460		192,460		167,696
Less accumulated depreciation and amortization	(107,128)		(107,128)		(96,198)
Fixed assets, net	85,332		85,332		71,498
Depreciation and amortization of furniture and equipment, and leasehold improvements	$ 6,500	$ 6,200	$ 12,070	$ 11,579

The cumulative amount of depreciation, depletion and amortization (related to property, plant and equipment, but not including land) that has been recognized in the income statement.

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Gross amount, as of the balance sheet date, of long-lived, depreciable assets that include building structures held for productive use including any addition, improvement, or renovation to the structure, such as interior masonry, interior flooring, electrical, and plumbing.

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- Definition

Gross amount, at the balance sheet date, of long-lived physical assets used in the normal conduct of business and not intended for resale. This can include land, buildings, machinery and equipment, and other types of furniture and equipment including, but not limited to, office equipment, furniture and fixtures, and computer equipment and software.

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- Definition

Tangible assets that are held by an entity for use in the production or supply of goods and services, for rental to others, or for administrative purposes and that are expected to provide economic benefit for more than one year; net of accumulated depreciation. Examples include land, buildings, machinery and equipment, and other types of furniture and equipment including, but not limited to, office equipment, furniture and fixtures, and computer equipment and software.

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