Investments - Schedule for Cost and Equity Method Investments (Details) - USD ($)	3 Months Ended			6 Months Ended		12 Months Ended
	Jun. 30, 2015	Dec. 31, 2014	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Schedule of Equity Method Investments [Line Items]
Other investments	$ 2,463,000	$ 24,639,000		$ 2,463,000		$ 24,639,000
Equity in loss of unconsolidated affiliate	998,000		$ 681,000	1,481,000	$ 1,160,000
Impairment on preferred shares	20,696,000			20,696,000
Synthonics
Schedule of Equity Method Investments [Line Items]
Cost method investments	$ 2,170,000	$ 2,170,000		$ 2,170,000		$ 2,170,000
Cost method, ownership percentage	18.30%	19.60%		18.30%		19.60%
Mindjet
Schedule of Equity Method Investments [Line Items]
Other investments	$ 4,000,000			$ 4,000,000
Voting interest percentage	28.40%			28.40%
Impairment on preferred shares	$ 20,700,000	$ 1,100,000
Minimum damages	0			$ 0
Maximum damages	1,200,000			1,200,000
Equity Securities
Schedule of Equity Method Investments [Line Items]
Marketable equity securities, carrying value	18,225,000	21,990,000		18,225,000		$ 21,990,000
Equity Securities | Mindjet
Schedule of Equity Method Investments [Line Items]
Cost method investments	$ 197,000	$ 15,858,000		$ 197,000		$ 15,858,000
Cost method, ownership percentage	13.40%	13.40%		13.40%		13.40%
Equity method investments	$ 96,000	$ 6,611,000		$ 96,000		$ 6,611,000
Equity method investments, ownership percentage	15.00%	15.00%		15.00%		15.00%
Other investments	$ 293,000	$ 22,469,000		$ 293,000		$ 22,469,000
Voting interest percentage	28.40%	28.40%		28.40%		28.40%
Convertible Debt Securities | Mindjet
Schedule of Equity Method Investments [Line Items]
Purchased convertible debt						$ 2,700,000
Conversion ratio				3
Investment interest rate				10.00%