FAIR VALUE MEASUREMENTS Table 2 (Details) (NS unit options [Member])	Jun. 30, 2014	Dec. 31, 2013
NS unit options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected life in years	5.9	5.8
Expected volatility	26.70%	26.40%
Expected distribution yield	7.10%	8.60%
Risk-free interest rate	0.10%	0.10%

The weighted-average period of time share-based awards, for an entity accounted for under the equity method, are expected to be outstanding. A share-based award's expected term shall be determined based on, among other factors, the instrument's contractual term and the effects of employees' expected exercise and post-vesting employment termination behavior. An entity is required to aggregate individual awards into relatively homogeneous groups.

No definition available.

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