Fair Value Measurements (Tables)

3 Months Ended

Mar. 31, 2013

Fair Value Measurements [Abstract]

Schedule of financial instruments measured at fair value on a recurring basis

	March 31, 2013
	Fair value measurements using
	Quoted Prices in		Significant		Significant
	Active Markets		Other		Unobservable
	for Identical		Observable		Inputs
	Assets		Inputs
	(Level 1)		(Level 2)		(Level 3)		Total
	(In thousands)
Assets:
U.S. Treasury securities	$	0	$	33,994	$	0	$	33,994
Money market accounts		8,047		0		0		8,047
Total assets at fair value	$	8,047	$	33,994	$	0	$	42,041

      The above table excludes $22.2 million of cash held in banks.

	December 31, 2012
	Fair value measurements using
	Quoted Prices in		Significant		Significant
	Active Markets		Other		Unobservable
	for Identical		Observable		Inputs
	Assets		Inputs
	(Level 1)		(Level 2)		(Level 3)		Total
	(In thousands)
Assets:
U.S. Treasury securities	$	0	$	38,988	$	0	$	38,988
Money market accounts		52		0		0		52
Total assets at fair value	$	52	$	38,988	$	0	$	39,040

 The above table excludes $4.5 million of cash held in banks.

Schedule of short-term investments

Short-term Investments

	March 31, 2013
	Amortized Cost	Gross Unrealized Holding Gains		Gross Unrealized Holding Losses		Fair Value
	(In thousands)
U.S. Treasury securities	$ 33,990	$	4	$	0	$  33,994
Total	$ 33,990	$	4	$	0	$  33,994
	December 31, 2012
	Amortized Cost	Gross Unrealized Holding Gains		Gross Unrealized Holding Losses		Fair Value
	(In thousands)
U.S. Treasury securities	$  38,980	$	8	$	0	$  38,988
Total	$  38,980	$	8	$	0	$  38,988