Transactions with Affiliates (Details) (USD $)	9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Dec. 31, 2011
Chairman and Chief Executive Officer, and Certain Family Partnerships and Affiliates [Member]
Related Party Transaction [Line Items]
Investment commitments with related party	$ 18,300,000	$ 20,700,000
Due to related parties, current	68,000		58,000
Overhead recovery from related parties	113,000	126,000
Expense reimbursements from related parties	113,000	126,000
Other Affiliated Entities [Member]
Related Party Transaction [Line Items]
Overhead recovery from related parties	73,000	89,000
Expense reimbursements to related parties	52,000	34,000
Expense reimbursements from related parties	73,000	89,000
Estimated annual rental expense	480,000
Lease Term	7 years
Rent expense paid	$ 322,000