Supplemental Guarantor Condensed Consolidating Financial Statements (Details 3) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Cash flows from operating activities
Net cash (used in) provided by operating activities	$ (113,915)	$ 53,146
Cash flows from investing activities
Acquisitions	(405,478)
Capital expenditures	(14,045)	(13,075)
Proceeds from sale of property and equipment	1,044	1,746
Net cash used in investing activities	(418,479)	(11,329)
Cash flows from financing activities
Borrowings from (payments on) working capital revolving credit facility	175,400	(20,200)
Borrowings from revolving credit facility	383,600
Payments on line of credit	(700)us-gaap_RepaymentsOfLinesOfCredit
Repurchase of common units	(2,442)
Noncontrolling interest capital contribution	1,880	2,400
Distribution to noncontrolling interest	(1,880)us-gaap_PaymentsToMinorityShareholders	(2,400)us-gaap_PaymentsToMinorityShareholders
Distributions to partners	(22,357)us-gaap_PaymentsOfCapitalDistribution	(17,770)us-gaap_PaymentsOfCapitalDistribution
Net cash provided by (used in) financing activities	533,501	(37,970)
Cash and cash equivalents
Increase in cash and cash equivalents	1,107	3,847
Cash and cash equivalents at beginning of period	5,238	9,217
Cash and cash equivalents at end of period	6,345	13,064
Eliminations
Cash and cash equivalents
Cash and cash equivalents at beginning of period			1,082
Cash and cash equivalents at end of period			1,082
(Issuer) Guarantor Subsidiaries
Cash flows from operating activities
Net cash (used in) provided by operating activities	(117,146)	48,362
Cash flows from investing activities
Acquisitions	(405,478)
Capital expenditures	(12,712)	(12,301)
Proceeds from sale of property and equipment	1,044	1,746
Net cash used in investing activities	(417,146)	(10,555)
Cash flows from financing activities
Borrowings from (payments on) working capital revolving credit facility	175,400	(20,200)
Borrowings from revolving credit facility	383,600
Repurchase of common units	(2,442)
Noncontrolling interest capital contribution	1,880	2,400
Distribution to noncontrolling interest	(1,880)	(2,400)
Distributions to partners	(22,357)	(17,770)
Net cash provided by (used in) financing activities	534,201	(37,970)
Cash and cash equivalents
Increase in cash and cash equivalents	(91)	(163)
Cash and cash equivalents at beginning of period	1,478	8,371
Cash and cash equivalents at end of period	2,469	8,208
Non-Guarantor Subsidiary
Cash flows from operating activities
Net cash (used in) provided by operating activities	3,231	4,784
Cash flows from investing activities
Capital expenditures	(1,333)	(774)
Net cash used in investing activities	(1,333)	(774)
Cash flows from financing activities
Payments on line of credit	(700)
Net cash provided by (used in) financing activities	(700)
Cash and cash equivalents
Increase in cash and cash equivalents	1,198	4,010
Cash and cash equivalents at beginning of period	2,678	846
Cash and cash equivalents at end of period	$ 3,876	$ 4,856

The net cash inflow (outflow) due to borrowings from (payments on) revolving credit facilities.

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The cash outflow to reacquire common units during the period.

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This element represents the payments on borrowings from working capital revolving credit facility during the reporting period.

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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The increase (decrease) in cash associated with the entity's continuing operating, investing, and financing activities. While for technical reasons this element has no balance attribute, the default assumption is a debit balance consistent with its label.

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Amount of cash inflow (outflow) of financing activities, excluding discontinued operations. Financing activity cash flows include obtaining resources from owners and providing them with a return on, and a return of, their investment; borrowing money and repaying amounts borrowed, or settling the obligation; and obtaining and paying for other resources obtained from creditors on long-term credit.

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Amount of cash inflow (outflow) of investing activities, excluding discontinued operations. Investing activity cash flows include making and collecting loans and acquiring and disposing of debt or equity instruments and property, plant, and equipment and other productive assets.

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Amount of cash inflow (outflow) from operating activities, excluding discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities.

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Cash outflow to owners or shareholders, excluding ordinary dividends. Includes special dividends.

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The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

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The cash outflow for purchases of and capital improvements on property, plant and equipment (capital expenditures), software, and other intangible assets.

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Amount of cash outflow to a noncontrolling interest. Includes, but not limited to, reduction of noncontrolling interest ownership. Excludes dividends paid to the noncontrolling interest.

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Amount of cash inflow from a noncontrolling interest. Includes, but is not limited to, purchase of additional shares or other increase in noncontrolling interest ownership.

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The cash inflow from the sale of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale.

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Amount of cash outflow for payment of an obligation from a lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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