CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
CONSOLIDATED BALANCE SHEETS [Abstract]
Allowance for doubtful accounts	$ 2,813	$ 5,576
Common stock, par value	$ 1	$ 1
Common stock, shares authorized	480,000,000	480,000,000
Common stock, shares outstanding	132,339,000	133,172,000