Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income (loss)	$ 111,082	$ 421,585	$ 106,202
Adjustments to reconcile net income to net cash provided by operating activities -
Depreciation and amortization	222,196	150,140	90,908
Gain on basis step up on historical interest	0	(332,380)	0
Amortization and write-off of debt issuance costs and premium	10,138	10,881	4,785
Amortization of unearned income and initial direct costs on direct financing leases	(14,395)	(14,979)	(15,706)
Payments received under direct financing leases	20,672	20,664	21,235
Equity in earnings of investments in equity investees	(47,944)	(54,450)	(43,135)
Cash distributions of earnings of equity investees	65,867	71,823	57,165
Non-cash effect of equity-based compensation plans	6,558	5,014	4,494
Deferred and other tax benefits	2,142	2,960	1,745
Unrealized (gains) losses on derivative transactions	1,287	(1,009)	(17,984)
Other, net	11,385	3,915	3,391
Net changes in components of operating assets and liabilities, net of acquisitions	(90,650)	5,372	77,954
Net cash provided by operating activities	298,338	289,536	291,054
CASH FLOWS FROM INVESTING ACTIVITIES:
Payments to acquire fixed and intangible assets	(463,100)	(495,774)	(443,482)
Cash distributions received from equity investees—return of investment	21,353	25,645	18,363
Investments in equity investees	0	(3,045)	(40,926)
Acquisitions	(25,394)	(1,520,299)	(157,000)
Contributions in aid of construction costs	13,374	3,179	0
Proceeds from asset sales and discontinued operations	3,609	2,811	272
Other, net	(151)	(1,976)	(1,214)
Net cash used in investing activities	(450,309)	(1,989,459)	(623,987)
CASH FLOWS FROM FINANCING ACTIVITIES:
Borrowings on senior secured credit facility	1,115,800	1,525,050	1,839,900
Repayments on senior secured credit facility	(952,600)	(960,450)	(1,872,300)
Proceeds from issuance of senior unsecured notes, including discount	0	1,139,718	350,000
Repayment of senior unsecured notes	0	(350,000)	0
Debt issuance costs	(1,578)	(28,901)	(11,896)
Issuance of common units for cash, net	298,020	633,759	225,725
Contributions (distributions) from (to) noncontrolling interests	236	(960)	0
Distributions to common unitholders	(310,039)	(256,389)	(200,461)
Other, net	(1,734)	(471)	2,561
Net cash provided by financing activities	148,105	1,701,356	333,529
Net increase (decrease) in cash and cash equivalents	(3,866)	1,433	596
Cash and cash equivalents at beginning of period	10,895	9,462	8,866
Cash and cash equivalents at end of period	$ 7,029	$ 10,895	$ 9,462