Summary of Significant Accounting Policies (Details)	6 Months Ended
Jun. 30, 2015
Principles of Consolidation
Ownership interest in consolidated subsidiaries (as a percent)	100.00%

The number of units or percentage investment held in the subsidiary by the limited liability company or limited partnership.

No definition available.

Name:	us-gaap_SubsidiaryOfLimitedLiabilityCompanyOrLimitedPartnershipOwnershipInterest
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration