ACCOUNTS PAYABLE AND ACCRUED LIABILITIES (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Jan. 01, 2018	Dec. 31, 2017
ACCOUNTS PAYABLE AND ACCRUED LIABILITIES.
Accounts payable, principally trade	$ 164,528		$ 153,862
Accrued employee compensation costs	168,349		144,175
Customer deposits and other unearned income	67,775		45,196
Other accrued liabilities	124,547		118,346
Total	$ 525,199	$ 455,873	$ 461,579