Related Party Transactions - Schedule of Other Related Party Balances (Details) - USD ($) $ in Millions		Dec. 31, 2015	Dec. 31, 2014
Related Party Transactions [Abstract]
Accounts receivable		$ 9.8	$ 16.1	[1]
Prepaid expenses		2.8	2.5
Other assets		0.6	0.5
Total assets		13.2	19.1
Accounts payable	[2]	9.3	11.0	[1]
Distribution payable to SPLC		0.0	11.9	[1]
Deferred revenue		3.6	4.7	[1]
Accrued liabilities	[3]	3.6	1.4	[1]
Debt payable		458.2
Total liabilities		$ 474.7	$ 29.0

[1] Prior period financial information has been retrospectively adjusted for the acquisition of the Shell Auger and Lockport Operations.

[2] Accounts payable – related parties reflects amounts owed to SPLC for reimbursement of third-party expenses incurred by SPLC for our benefit.

[3] Accrued liabilities -- related parties reflects $1.3 million accrued interest, $1.2 million fuel accrual, $0.6 FERC accrual and $0.5 million other accrued liabilities