CONSOLIDATED BALANCE SHEETS - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Current Assets:
Cash and cash equivalents	$ 17.6	$ 4.6
Receivables:
Trade, net	116.8	127.1
Other	16.6	12.7
Gas transportation receivables	4.6	8.2
Gas and liquids stored underground	6.5	1.3
Prepayments	17.9	17.7
Other current assets	0.6	2.6
Total current assets	180.6	174.2
Property, Plant and Equipment:
Natural gas transmission and other plant	10,467.1	9,958.8
Construction work in progress	416.5	368.5
Property, plant and equipment, gross	10,883.6	10,327.3
Less—accumulated depreciation and amortization	2,621.1	2,333.8
Property, plant and equipment, net	8,262.5	7,993.5
Other Assets:
Goodwill	237.4	237.4
Gas stored underground	86.3	93.5
Other	139.8	139.2
Total other assets	463.5	470.1
Total Assets	8,906.6	8,637.8
Payables:
Trade	76.0	113.8
Affiliates	1.5	1.4
Other	11.9	23.7
Gas payables	5.7	6.7
Accrued taxes, other	57.1	52.7
Accrued interest	37.9	40.6
Accrued payroll and employee benefits	33.7	38.5
Construction retainage	32.4	19.6
Deferred income	1.9	7.5
Other current liabilities	22.3	28.4
Total current liabilities	280.4	332.9
Long–term debt and capital lease obligation	3,686.8	3,558.0
Other Liabilities and Deferred Credits:
Pension liability	21.8	22.0
Asset retirement obligation	46.0	44.7
Provision for other asset retirement	65.8	63.7
Payable to affiliate	16.0	16.0
Other	65.0	69.6
Total other liabilities and deferred credits	214.6	216.0
Commitments and Contingencies
Partners’ Capital:
Common units – 250.3 million units issued and outstanding as of December 31, 2017 and 2016	4,713.1	4,522.2
General partner	92.7	88.8
Accumulated other comprehensive loss	(81.0)	(80.1)
Total partners’ capital	4,724.8	4,530.9
Total Liabilities and Partners' Capital	$ 8,906.6	$ 8,637.8