Marketable Securities (Tables)

6 Months Ended

Jun. 30, 2012

Fair Value Hierarchy of Assets Measured on Recurring Basis

The following table presents the placement in the fair value hierarchy of assets that are measured at fair value on a recurring basis at period end:

June 30, 2012:	Total		Level 1		Level 2		Level 3
Common stock	$	310		310		0		0
Government and agency securities		26,856		26,856		0		0
Total available-for-sale securities	$	27,166		27,166		0		0

December 31, 2011:	Total		Level 1		Level 2		Level 3
Common stock	$	320		320		0		0
Government and agency securities		26,845		26,845		0		0
Total available-for-sale securities	$	27,165		27,165		0		0

June 30, 2011:	Total		Level 1		Level 2		Level 3
Common stock	$	344		344		0		0
Government and agency securities		25,899		25,899		0		0
Total available-for-sale securities	$	26,243		26,243		0		0

Summary of Marketable Securities Treated as Available-for-Sale Securities

Marketable securities, all treated as available-for-sale securities at period end, consist of the following:

June 30, 2012:	Amortized cost		Gross unrealized gains		Gross unrealized losses			Fair value
Common stock	$	197		113		0			310
Government and agency securities		26,862		0		(6	)		26,856
Total available-for-sale securities	$	27,059		113		(6	)		27,166

December 31, 2011:	Amortized cost		Gross unrealized gains		Gross unrealized losses			Fair value
Common stock	$	197		123		0			320
Government and agency securities		26,851		0		(6	)		26,845
Total available-for-sale securities	$	27,048		123		(6	)		27,165

June 30, 2011:	Amortized cost		Gross unrealized gains		Gross unrealized losses		Fair value
Common stock	$	198		146		0		344
Government and agency securities		25,850		49		0		25,899
Total available-for-sale securities	$	26,048		195		0		26,243

Summary of Future Maturities of Available-For-Sale Securities

Future maturities of our available-for-sale securities consist of the following:

	Less than 12 months				Greater than 12 months
	Amortized		Fair		Amortized		Fair
June 30, 2012:	cost		value		cost		value
Common stock	$	197		310		0		0
Government and agency securities		26,862		26,856		0		0
Total available-for-sale securities	$	27,059		27,166		0		0