Consolidated Statements Of Cash Flows (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income (loss)	$ 96,319	$ 51,249	$ (50,541)
Adjustments to reconcile net income to net cash provided by operating activities -
Depreciation and amortization	61,166	62,190	53,569
Amortization and write-off of debt issuance costs and premium	4,037	2,940	3,082
Amortization of unearned income and initial direct costs on direct financing leases	(16,788)	(17,237)	(17,651)
Payments received under direct financing leases	21,804	21,852	21,854
Equity in earnings of investments in equity investees	(14,345)	(3,347)	(2,355)
Cash distributions of earnings of equity investees	23,900	8,592	3,623
Non-cash effect of equity-based compensation plans	7,197	(15)	4,706
Non-cash compensation charge	0	0	76,923
Deferred and other tax (benefits) liabilities	(9,222)	(2,075)	1,337
Unrealized losses on derivative transactions	86	1,002	1,562
Other, net	2,085	87	(159)
Net changes in components of operating assets and liabilities, net of acquisitions (See Note 14)	13,065	(66,931)	(5,487)
Net cash provided by operating activities	189,304	58,307	90,463
CASH FLOWS FROM INVESTING ACTIVITIES:
Payments to acquire fixed and intangible assets	(146,456)	(27,992)	(12,400)
Cash distributions received from equity investees—return of investment	14,909	11,436	2,859
Investments in equity investees	(63,749)	0	0
Acquisitions	(205,576)	(163,673)	(332,462)
Proceeds from asset sales	773	6,424	1,146
Other, net	(1,508)	1,508	119
Net cash used in investing activities	(401,607)	(172,297)	(340,738)
CASH FLOWS FROM FINANCING ACTIVITIES:
Borrowings on senior secured credit facility	1,674,400	777,600	691,829
Repayments on senior secured credit facility	(1,583,700)	(728,300)	(698,729)
Proceeds from issuance of senior unsecured notes, including premium	101,000	0	250,000
Debt issuance costs	(7,105)	(3,018)	(14,586)
Issuance of common units for cash, net	169,421	184,969	116,347
General partner contributions	0	0	2,528
Distributions to common unitholders	(142,383)	(112,844)	(58,983)
Distributions to general partner interest	0	0	(11,369)
Acquisition of noncontrolling interest in DG Marine	0	0	(26,288)
Other, net	1,135	638	1,140
Net cash provided by financing activities	212,768	119,045	251,889
Net increase in cash and cash equivalents	465	5,055	1,614
Cash and cash equivalents at beginning of period	10,817	5,762	4,148
Cash and cash equivalents at end of period	$ 11,282	$ 10,817	$ 5,762