Annual report pursuant to Section 13 and 15(d)

FAIR VALUE MEASUREMENT (Details)

v3.8.0.1
FAIR VALUE MEASUREMENT (Details)
$ in Thousands
Dec. 31, 2017
USD ($)
insurance_policy
Dec. 31, 2016
USD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Number of life insurance policies | insurance_policy 70  
Life insurance policies, net face value $ 43,400  
Cash surrender value of life insurance policies 18,300 $ 15,700
Deferred compensation assets 18,400 15,900
Deferred compensation plan | Estimate of Fair Value, Fair Value Disclosure    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Cash and cash equivalents 95 188
Total fair value 95 188
Deferred compensation plan | Level 1    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Cash and cash equivalents 95 188
Total fair value $ 95 $ 188