Summary of Significant Accounting Policies (Tables)

6 Months Ended

Jun. 30, 2013

Summary of Significant Accounting Policies

Schedule of non-controlling interest in subsidiary

(in thousands)	Non-Controlling Interest
Balance at December 31, 2011	$	574
Net loss attributable to Silver Creek	(231		)
Balance at June 30, 2012	$	343

	Non-Controlling Interest (Deficit)
Balance at December 31, 2012	$	97
Net loss attributable to Silver Creek	(339		)
Balance at June 30, 2013	$	(242	)

Schedule of available-for-sale securities, all of which have maturities of twelve months or less

	Amortized Cost		Unrealized Gains		Unrealized Losses			Fair Value
	(in thousands)
June 30, 2013:
Certificate of deposit	$	1,200	$	—	$	(1	)	$	1,199
Commercial paper	7,996		1		—			7,997
Corporate debt securities	22,006		—		(5		)	22,001
Total	$	31,202	$	1	$	(6	)	$	31,197

Schedule of available-for-sale securities in an unrealized loss position

	Aggregate Fair Value		Unrealized Losses
	(in thousands)
June 30, 2013:
Certificate of deposit	$	1,199	$	(1	)
Corporate debt securities	17,992		(5		)
	$	19,191	$	(6	)