Fair Value Measurement (Tables)

12 Months Ended

Dec. 31, 2011

Fair Value Disclosures [Abstract]

Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block]

The following tables summarize each class of assets and liabilities measured at fair value on a recurring basis (in thousands):

	Fair Value Measurement at Reporting Date Using
December 31, 2011	Level 11		Level 22		Level 33		Total
Cash equivalents
Money market funds	$	178,174	$	—	$	—	$	178,174
Total	$	178,174	$	—	$	—	$	178,174

December 31, 2010
Cash equivalents
Money market funds	$	226,009	$	—	$	—	$	226,009
Trading securities
Equity securities - mutual funds	14,411		—		—		14,411
Total	$	240,420	$	—	$	—	$	240,420

¹Quoted prices in active markets for identical assets or liabilities.

²Observable inputs other than Level 1 prices such as quoted prices for similar assets or liabilities; quoted prices in markets that are not active; or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities.

³Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities.

Schedule of Cash and Cash Equivalents [Table Text Block]

A reconciliation of money market funds to consolidated cash and cash equivalents is as follows (in thousands):

December 31,	2011		2010
Money market funds	$	178,174	$	226,009
Held-to-maturity commercial paper	4,999		4,999
Cash	73,817		21,014
Total cash and cash equivalents	$	256,990	$	252,022

Fair Value, by Balance Sheet Grouping [Table Text Block]

The carrying amount and estimated fair value of senior notes payable, including current maturities, were as follows (in thousands):

December 31,	2011		2010
Carrying amount
Senior notes payable (including current maturities)	$	216,666	$	225,000
Fair value
Senior notes payable (including current maturities)	$	250,541	$	245,015