UNIT-BASED COMPENSATION PLANS (Detail 3) (Option Plan, LP Units, USD $) Share data in Thousands, except Per Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014
Option Plan \| LP Units
Change in the options outstanding
Beginning Balance	26
Exercised	(2)
Ending Balance	24	26
Exercisable at March 31, 2015	24
Weighted-Average Strike Price LP Unit
Beginning Balance	$ 48.18
Exercised	$ 45.88
Ending Balance	$ 48.36	$ 48.18
Exercisable at March 31, 2015	$ 48.36
Weighted-Average Remaining Contractual Term (in years)
Beginning Balance	1 year 4 months 24 days	1 year 7 months 6 days
Ending Balance	1 year 4 months 24 days	1 year 7 months 6 days
Exercisable at March 31, 2015	1 year 4 months 24 days
Aggregate Intrinsic Value
Outstanding at period beginning	$ 703,000
Outstanding at period end	647,000	703,000
Exercisable at March 31, 2015	647,000
Additional disclosures
Total intrinsic value of options exercised	$ 100,000		$ 100,000

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of fully vested and expected to vest options outstanding.

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As of the balance sheet date, the number of shares into which fully vested and expected to vest stock options outstanding can be converted under the option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Number of share options (or share units) exercised during the current period.

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