Acquisitions (Rangely Acquisition) (Narrative) (Details) (USD $)	3 Months Ended	1 Months Ended
	Mar. 31, 2014	Jun. 30, 2014 Rangely Acquisition	May 31, 2014 Rangely Acquisition
Business Acquisition [Line Items]
Business Acquisition, Date of Acquisition Agreement		Jun. 30, 2014
Business Acquisition, Percentage of Voting Interests Acquired		25.00%
Business Acquisition, Name of Acquired Entity		Rangely Acquisition
Business Acquisition, Cost of Acquired Entity, Cash Paid		$ 420,000,000
Senior notes, interest rate		7.75%
Senior Notes		100,000,000
Partners' Capital Account, Units, Sale of Units	6,325,000	15,525,000	15,525,000
Business Acquisition, Purchase Price Allocation, Methodology		The Partnership accounted for this transaction under the acquisition method of accounting. Accordingly, the Partnership evaluated the identifiable assets acquired and liabilities assumed at their respective acquisition date fair values (see Note 9).
Business Acquisition, Purchase Price Allocation, Status		In conjunction with the issuance of common limited partner units associated with the acquisition, the Partnership recorded $11.5 million of transaction fees which were included with common limited partners’ interests for the six months ended June 30, 2014 on the Partnership’s consolidated balance sheet. All other costs associated with the acquisition of assets were expensed as incurred. Due to the recent date of the acquisition, the accounting for the business combination is based upon preliminary data that remains subject to adjustment and could further change as the Partnership continues to evaluate the facts and circumstances that existed as of the acquisition date.
Business Acquisition, Cost of Acquired Entity, Transaction Costs		$ 11,500,000