Available for Sale Investments (Tables)

6 Months Ended

Jun. 30, 2012

Available for Sale Investments [Abstract]

Estimated Fair Value of Available-for-Sale Short-Term Investments by Security Classification

December 31, 2011 (In thousands)	Amortized Costs		Gross Unrealized Gains		Gross Unrealized Losses		Estimated Fair Values
Government-sponsored securities	$	993	$	—	$	—	$	993
Corporate debt securities		1,086		—		—		1,086
Total securities	$	2,079	$	—	$	—	$	2,079