v2.4.0.8

ALLOWANCE FOR DOUBTFUL ACCOUNTS | 12 Months Ended
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Dec. 31, 2013
ALLOWANCE FOR DOUBTFUL ACCOUNTS [Abstract] |
Allowance for Doubtful Accounts [Text Block] | ALLOWANCE FOR DOUBTFUL ACCOUNTS The changes in the allowance for doubtful accounts consisted of the following:
| Year Ended December 31,
| 2013 |  | 2012 |  | 2011
| (Thousands of Dollars)
Balance as of beginning of year | $ | 808 |  |  | $ | 2,147 |  |  | $ | 1,457 |
Increase in allowance | 1,039 |  |  | 27 |  |  | 934 |
Accounts charged against the allowance, net of recoveries | (625 | ) |  | (1,367 | ) |  | (243 | )
Foreign currency translation | 2 |  |  | 1 |  |  | (1 | )
Balance as of end of year | $ | 1,224 |  |  | $ | 808 |  |  | $ | 2,147 |

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- Details
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Namespace Prefix: | ns_
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Balance Type: | na
Period Type: | duration

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- Definition The entire disclosure for allowance for credit losses. + References No definition available. + Details
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Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration