Summary of Significant Accounting Policies (Details) - Jun. 30, 2015 - USD ($) $ in Millions	Total
Held by Wells Fargo Bank N.A. [Member]
Summary of Significant Accounting Policies (Details) [Line Items]
Investments and Cash	$ 1.5
Maximum [Member]
Summary of Significant Accounting Policies (Details) [Line Items]
Offering Costs as Percentage of Month-end Net Asset Value	0.50%

Sum of investments and unrestricted cash as of the balance sheet date.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.1,2)

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Name:	us-gaap_InvestmentsAndCash
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant