Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Statement of Financial Position [Abstract]
Accounts and notes receivable, allowances	$ 12,719	$ 13,306
Property and equipment, accumulated depreciation	$ 186,580	$ 163,377
Common stock, par value (in dollars per share)	$ 2	$ 2
Common stock, authorized	200,000,000	200,000,000
Common stock, issued	62,932,000	63,070,000
Common stock, outstanding	62,932,000	63,070,000