CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
CONSOLIDATED BALANCE SHEETS [Abstract]
Customers, allowance for doubtful accounts	$ 5,576	$ 5,105
Common stock, par value	$ 1	$ 1
Common stock, shares authorized	480,000,000	480,000,000
Common stock, shares outstanding	133,172,000	131,907,000