Subsequent Event	3 Months Ended
Mar. 31, 2013
Subsequent events [Abstract]
Subsequent Events	(13) Subsequent Event On May 8, 2013, Subsidiary Borrower exercised the accordion feature of the Subsidiary Credit Agreement, thereby increasing the amount Subsidiary Borrower is permitted to borrow on a revolving credit basis from $75.0 million to $90.0 million. Subsidiary Borrower intends to distribute these additional funds to the Company for its additional $25.0 million investment commitment in E2 for the construction of a third natural gas compression and condensate stabilization facility in the Ohio River Valley.

The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

No definition available.

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