Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2016	Dec. 31, 2015
Statement of Financial Position [Abstract]
Allowance for Doubtful Accounts Receivable	$ 10,722	$ 9,997
Allowance for Notes, Loans and Financing Receivable, Current	13,033	15,480
Allowance for Notes, Loans and Financing Receivable, Noncurrent	$ 5,092	$ 6,210
Preferred stock par value (in dollars per share)	$ 50	$ 50
Preferred stock dividend rate	4.00%
Preference stock dividend rate (in dollars per share)	$ 2.12	2.12
Common stock, par value (in dollars per share)	$ 1	$ 1
Common stock, shares authorized	480,000,000	480,000,000
Common stock, shares issued	323,337,912	323,337,912
Treasury stock, shares	137,701,038	127,816,704