Commitments and Contingencies (Details) $ in Thousands	Apr. 25, 2016 lawsuit	Mar. 01, 2016 lawsuit defendant	Mar. 31, 2016 USD ($)	Mar. 31, 2015 USD ($)
Other Commitments [Line Items]
Monthly percentage of effective management fee percentage			8.33%
Gross equity raised | $			$ 2,469,368	$ 2,663,917
Transactions
Other Commitments [Line Items]
Number of new claims filed		9
Number of defendants that are current directors | defendant		8
Transactions | Subsequent Event
Other Commitments [Line Items]
Number of consolidated claims	1
ACM
Other Commitments [Line Items]
Percentage of gross equity raised used in calculation of management fee up to 1 Billion			1.50%
Percentage of gross equity raised used in calculation of management fee in excess of 1 Billion			0.75%
Effective management fee			1.05%	1.03%