Investments (Details) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013
Schedule of Available-for-sale Securities
Debt securities, Cost	$ 8,426,000		$ 8,426,000		$ 8,988,000
Debt securities, Carrying Value	8,587,000		8,587,000		9,172,000
Total, Cost	29,261,000		29,261,000		40,011,000
Total, Gross Unrealized Gains	10,143,000		10,143,000		11,048,000
Total, Gross Unrealized Losses	(107,000)		(107,000)		(479,000)
Total, Carrying Value	39,297,000		39,297,000		50,580,000
Available-for-sale Securities, Continuous Unrealized Loss Position
Less than 12 months, fair value	5,103,000		5,103,000		4,453,000
Less than 12 months, Gross Unrealized Loss	87,000		87,000		254,000
Greater than 12 months, fair value	241,000		241,000		8,112,000
Greater than 12 months, Gross Unrealized Loss	20,000		20,000		225,000
Available-for-sale Securities, Debt Maturities [Abstract]
Due in one year or less, Amortized Cost	3,165,000		3,165,000		68,000
Due after one year through five years, Amortized Cost	2,533,000		2,533,000		5,981,000
Due after five years, Amortized Cost	2,728,000		2,728,000		2,939,000
Due in one year or less, Carrying Value	3,356,000		3,356,000		68,000
Due after one year through five years, Carrying Value	2,552,000		2,552,000		6,178,000
Due after five years, Carrying Value	2,679,000		2,679,000		2,926,000
Other Investments [Abstract]
Equity in loss of unconsolidated affiliate	(410,000)	(89,000)	(1,569,000)	(89,000)
Mindjet
Other Investments [Abstract]
Voting Interest Percentage	28.60%		28.60%
Equity Method Investment, Ownership Percentage	15.10%		15.10%
Cost Method, Ownership Percentage	13.50%		13.50%
Other Investments	26,200,000		26,200,000
Minimum estimated damages	0		0
Maximum estimated damages	1,200,000		1,200,000
Corporate Bond Securities
Schedule of Available-for-sale Securities
Debt securities, Cost	8,426,000		8,426,000		8,988,000
Debt securities, Gross Unrealized Gains	222,000		222,000		213,000
Debt securities, Gross Unrealized Losses	(61,000)		(61,000)		(29,000)
Debt securities, Carrying Value	8,587,000		8,587,000		9,172,000
Available-for-sale Securities, Continuous Unrealized Loss Position
Less than 12 months, fair value	3,088,000		3,088,000
Less than 12 months, Gross Unrealized Loss	61,000		61,000
Greater than 12 months, fair value					5,744,000
Greater than 12 months, Gross Unrealized Loss					29,000
Convertible Debt Securities | Mindjet
Other Investments [Abstract]
Payments to Acquire Held-to-maturity Securities	1,900,000
Escrow Deposit	761,000		761,000
Investment Interest Rate			10.00%
Convertible debt conversion ratio			3
Equity Securities
Schedule of Available-for-sale Securities
Marketable equity securities, Cost	20,835,000		20,835,000		31,023,000
Marketable equity securities, Gross Unrealized Gains	9,921,000		9,921,000		10,835,000
Marketable equity securities, Gross Unrealized Losses	(46,000)		(46,000)		(450,000)
Marketable equity securities, Carrying Value	30,710,000		30,710,000		41,408,000
Available-for-sale Securities, Continuous Unrealized Loss Position
Less than 12 months, fair value	2,015,000		2,015,000		4,453,000
Less than 12 months, Gross Unrealized Loss	26,000		26,000		254,000
Greater than 12 months, fair value	241,000		241,000		2,368,000
Greater than 12 months, Gross Unrealized Loss	20,000		20,000		196,000
Other Investments [Abstract]
Marketable equity securities, Carrying Value	$ 30,710,000		$ 30,710,000		$ 41,408,000