Note 11 - Equity and Net Earnings per Unit Equity, Changes in Equity (Details) - shares shares in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Partners' Capital Account, Units	219.9	105.1	95.4
Partners' Capital Account, Units, Sale of Units		5.1	6.3
Partners' Capital Account, Units, Unit-based Compensation	0.1		0.1
Partners' Capital Account, Units	248.3	219.9	105.1
Common
Partners' Capital Account, Units	217.1	103.0	93.5
Partners' Capital Account, Units, Sale of Units		5.0	6.3
Partners' Capital Account, Units, Unit-based Compensation	0.1		0.1
Partners' Capital Account, Units	245.5	217.1	103.0
Preferred
Partners' Capital Account, Units	0.6	0.0	0.0
Partners' Capital Account, Units, Sale of Units		0.0	0.0
Partners' Capital Account, Units, Unit-based Compensation	0.0		0.0
Partners' Capital Account, Units	0.6	0.6	0.0
General Partner
Partners' Capital Account, Units	2.2	2.1	1.9
Partners' Capital Account, Units, Sale of Units		0.1	0.0
Partners' Capital Account, Units, Unit-based Compensation	0.0		0.0
Partners' Capital Account, Units	2.2	2.2	2.1
Northern California Term. and Stor. Assets
Partners' Capital Account, Units, Acquisitions			0.9
Northern California Term. and Stor. Assets \| Common
Partners' Capital Account, Units, Acquisitions			0.9
Northern California Term. and Stor. Assets \| Preferred
Partners' Capital Account, Units, Acquisitions			0.0
Northern California Term. and Stor. Assets \| General Partner
Partners' Capital Account, Units, Acquisitions			0.0
Anacortes Logistics Assets
Partners' Capital Account, Units, Acquisitions		1.0
Anacortes Logistics Assets \| Common
Partners' Capital Account, Units, Acquisitions		1.0
Anacortes Logistics Assets \| Preferred
Partners' Capital Account, Units, Acquisitions		0.0
Anacortes Logistics Assets \| General Partner
Partners' Capital Account, Units, Acquisitions		0.0
ATM Program
Partners' Capital Account, Units, Sale of Units		0.1	1.4
ATM Program \| Common
Partners' Capital Account, Units, Sale of Units		0.1	1.4
ATM Program \| Preferred
Partners' Capital Account, Units, Sale of Units		0.0	0.0
ATM Program \| General Partner
Partners' Capital Account, Units, Sale of Units		0.0	0.0
Preferred Stock [Member]
Partners' Capital Account, Units, Sale of Units		0.6
Preferred Stock [Member] \| Common
Partners' Capital Account, Units, Sale of Units		0.0
Preferred Stock [Member] \| Preferred
Partners' Capital Account, Units, Sale of Units		0.6
Preferred Stock [Member] \| General Partner
Partners' Capital Account, Units, Sale of Units		0.0
Phase One \| Alaska Logistics Assets
Partners' Capital Account, Units, Acquisitions			0.6
Phase One \| Alaska Logistics Assets \| Common
Partners' Capital Account, Units, Acquisitions			0.4
Phase One \| Alaska Logistics Assets \| Preferred
Partners' Capital Account, Units, Acquisitions			0.0
Phase One \| Alaska Logistics Assets \| General Partner
Partners' Capital Account, Units, Acquisitions			0.2
Phase Two \| Alaska Logistics Assets
Partners' Capital Account, Units, Acquisitions			0.4
Phase Two \| Alaska Logistics Assets \| Common
Partners' Capital Account, Units, Acquisitions			0.4
Phase Two \| Alaska Logistics Assets \| Preferred
Partners' Capital Account, Units, Acquisitions			0.0
Phase Two \| Alaska Logistics Assets \| General Partner
Partners' Capital Account, Units, Acquisitions			0.0
WNRL Merger [Member]
Partners' Capital Account, Units, Acquisitions	28.3	108.0
WNRL Merger [Member] \| Common
Partners' Capital Account, Units, Acquisitions	28.3	108.0
WNRL Merger [Member] \| Preferred
Partners' Capital Account, Units, Acquisitions	0.0	0.0
WNRL Merger [Member] \| General Partner
Partners' Capital Account, Units, Acquisitions	0.0	0.0

The number of each class of partnership units outstanding at the balance sheet date. Units represent shares of ownership of the general, limited, and preferred partners.

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