Investments (Details) (USD $)	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2012
Investments
Fair value of investments	$ 21,597,000		$ 20,478,000
Investments (realized and unrealized gains/(losses))	172,000	132,000
Investment in FATV
Investments
Fair value of investments	17,251,000		17,110,000
Open commitments to fund portfolio	0
Total partnership capital	71,500,000		70,900,000
Share in management fee income	200,000	200,000
Employee Investment Funds net of Company's ownership interest
Investments
Fair value of investments	1,249,000		1,218,000
Other investments
Investments
Fair value of investments	$ 3,097,000		$ 2,150,000