XML 42 R50.htm IDEA: XBRL DOCUMENT v3.19.3.a.u2
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - SELLING, MARKETING AND ADMINISTRATIVE EXPENSE (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Accounting Policies [Abstract]      
Research and development costs $ 37,146 $ 38,521 $ 45,850
Advertising expense 513,302 479,908 $ 541,293
Prepaid advertising expense $ 242 $ 594