Marketable Securities (Tables)

12 Months Ended

Dec. 31, 2011

Marketable Securities [Abstract]

Amortized Cost And Estimated Fair Value Of Marketable Securities

	December 31, 2011								December 31, 2010
	Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value		Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
Available-for-Sale
Debt Securities:
Corporate Bonds	$	1,008	$	—	$	2	$	1,006	$	7,126	$	45	$	—	$	7,171
Municipal Bonds		9,544		9		—		9,553		16,910		107		15		17,002
Other Debt Securities		2,000		—		—		2,000		1,000		—		—		1,000
Seed Capital Investments		10,905		812		27		11,690		14,112		2,250		25		16,337
Total Available-for-Sale		23,457		821		29		24,249		39,148		2,402		40		41,510
Debt Securities Carried by EGL		47,583		518		—		48,101		50,837		501		18		51,320
Mutual Funds		9,350		191		603		8,938		—		—		—		—
Total	$	80,390	$	1,530	$	632	$	81,288	$	89,985	$	2,903	$	58	$	92,830

Scheduled Maturities Of Available-For-Sale Debt Securities

	December 31, 2011				December 31, 2010
	Amortized Cost		Fair Value		Amortized Cost		Fair Value
Due within one year	$	8,699	$	8,703	$	17,183	$	17,265
Due after one year through five years		3,853		3,856		7,853		7,908
Total	$	12,552	$	12,559	$	25,036	$	25,173