v3.8.0.1

UNIT-BASED COMPENSATION (Tables)

12 Months Ended

Dec. 31, 2017

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Summary of long-term incentive plan compensation expense

The following table summarizes information pertaining to our long-term incentive plan compensation expense:

	Units Outstanding December 31,						Transferred Units			Compensation Expense Year Ended December 31,
	2017			2016			March 1, 2016			2017				2016
										(Thousands of Dollars)
Restricted Units:
Domestic employees	736,746			647,340			586,524			$	7,881			$	5,980
Non-employee directors (NEDs)	27,097			18,134			17,629			251				388
International employees	58,107			50,609			49,121			595				715
Performance Units	80,961			77,014			77,014			—				1,211
Total	902,911			793,097			730,288			$	8,727			$	8,294

Restricted unit award activity

A summary of our restricted unit activity is as follows:

	Domestic Employees
	Number of Restricted Units			Weighted- Average Grant-Date Fair Value Per Unit				Number of Restricted Units to NEDs			Number of Restricted Units to International Employees
Nonvested units as of January 1, 2016	—			$	—			—			—
Transferred	586,524			35.03				17,629			49,121
Granted	246,070			47.70				8,730			20,107
Vested	(180,724	)		35.50				(8,225	)		(14,812	)
Forfeited	(4,530	)		35.03				—			(3,807	)
Nonvested units as of December 31, 2016	647,340			39.72				18,134			50,609
Granted	307,009			29.56				17,110			24,533
Vested	(201,466	)		38.74				(8,147	)		(16,440	)
Forfeited	(16,137	)		40.00				—			(595	)
Nonvested units as of December 31, 2017	736,746			$	35.95			27,097			58,107

Performance Units [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Summary of long-term incentive plan compensation expense

Performance units vested during the year ended December 31, 2017 with respect to 2016 performance were as follows:

	Vested Units			Actual Conversion Rate			Gross Number of Units Issued
2014 awards	9,613			150	%		14,420
2015 awards	9,878			150	%		14,818
2016 awards	15,882			150	%		23,825
Total	35,373						53,063

A summary of our performance units is shown below:

				Granted for Accounting Purposes
	Total Performance Units Awarded			Performance Units			Weighted-Average Grant Date Fair Value per Unit
Outstanding as of January 1, 2017	77,014			35,373			$	31.75
Granted	39,320			38,865			50.04
Vested	(35,373	)		(35,373	)		31.75
Outstanding as of December 31, 2017	80,961			38,865			$	50.04

X

- Definition

Tabular disclosure of components of a stock option or other award plan under which equity-based compensation is awarded to employees, typically comprised of the amount of unearned compensation (deferred compensation cost), compensation expense, and changes in the quantity and fair value of the shares (or other type of equity) granted, exercised, forfeited, and issued and outstanding pertaining to that plan. Disclosure may also include nature and general terms of such arrangements that existed during the period and potential effects of those arrangements on shareholders, effect of compensation cost arising from equity-based payment arrangements on the income statement, method of estimating the fair value of the goods or services received, or the fair value of the equity instruments granted, during the period, cash flow effects resulting from equity-based payment arrangements and, for registrants that accelerate vesting of out of the money share options, reasons for the decision to accelerate.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5047-113901

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- Definition

Tabular disclosure of the number and weighted-average grant date fair value for restricted stock units that were outstanding at the beginning and end of the year, and the number of restricted stock units that were granted, vested, or forfeited during the year.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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No definition available.

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