Consolidated Statements Of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Operating Activities:
Net income	$ 207,070	$ 183,636
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization expense	43,754	41,697
Loss (gain) on sale and retirement of assets	2,259	(3)
Earnings of non-controlled entities	(17,628)	(9,590)
Distributions of earnings from investments in non-controlled entities	17,297	9,229
Equity-based incentive compensation expense	6,650	4,751
Amortization of prior service credit and actuarial loss	428	644
Gain on exchange of interest in non-controlled entity	(26,900)	0
Changes in operating assets and liabilities:
Trade accounts receivable and other accounts receivable	(6,904)	(12,194)
Inventory	(1,220)	(3,187)
Energy commodity derivatives contracts, net of derivatives deposits	(132)	(5,804)
Accounts payable	1,052	(4,351)
Accrued payroll and benefits	(16,863)	(16,579)
Accrued interest payable	(3,365)	(173)
Accrued taxes other than income	(11,101)	(5,801)
Accrued product purchases	(9,674)	(6,402)
Deferred revenue	13,987	4,778
Current and noncurrent environmental liabilities	962	15
Other current and noncurrent assets and liabilities	9,896	10,417
Net cash provided by operating activities	209,568	191,083
Investing Activities:
Additions to property, plant and equipment, net(1)	(139,522)	(128,517)
Proceeds from sale and disposition of assets	17	3,089
Investments in non-controlled entities	(61,738)	(13,751)
Distributions in excess of earnings of non-controlled entities	2,212	4,613
Net cash used by investing activities	(199,031)	(134,566)
Financing Activities:
Distributions paid	(178,808)	(158,061)
Net commercial paper repayments	(279,961)	(296,942)
Borrowings under long-term notes	649,187	499,589
Debt placement costs	(5,318)	(4,661)
Net payment on financial derivatives	0	(42,908)
Settlement of tax withholdings on long-term incentive compensation	(14,376)	(17,784)
Net cash provided (used) by financing activities	170,724	(20,767)
Change in cash and cash equivalents	181,261	35,750
Cash and cash equivalents at beginning of period	28,731	17,063
Cash and cash equivalents at end of period	209,992	52,813
Supplemental non-cash investing and financing activities:
Contribution of property, plant and equipment to a non-controlled entity	0	13,252
Issuance of limited partner units in settlement of equity-based incentive plan awards	7,092	8,045
Additions to property, plant and equipment	(139,636)	(127,709)
Changes in accounts payable and other current liabilities related to capital expenditures	114	(808)
Additions to property, plant and equipment	$ (139,522)	$ (128,517)