XML 137 R61.htm IDEA: XBRL DOCUMENT v3.19.3.a.u2
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - New accounting standards (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2019
Jan. 01, 2019
New Accounting Pronouncements or Change in Accounting Principle [Line Items]    
Operating lease right-of-use assets $ 17,660  
Operating lease liabilities $ 17,567  
Lease, Practical Expedients, Package [true false] true  
Lease, Practical Expedient, Use of Hindsight [true false] true  
ASU 2016-02 | Adjustment    
New Accounting Pronouncements or Change in Accounting Principle [Line Items]    
Operating lease right-of-use assets   $ 25,000
Operating lease liabilities   $ 25,000