CONSOLIDATED STATEMENTS OF EQUITY - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-In Capital	Retained Earnings	Accumulated Other Comprehensive Income (Loss) [Member]	Treasury Shares	Noncontrolling Interests
Beginning Balance at Dec. 31, 2012	$ 1,358,321	$ 9,858	$ 205,124	$ 1,682,668	$ (235,400)	$ (319,877)	$ 15,948
Beginning Balance (in shares) at Dec. 31, 2012		82,945,000
Increase (Decrease) in Stockholders' Equity
Net income	291,687			293,780			(2,093)
Unrecognized amounts from defined benefit pension plans, net of tax	101,151				101,151
Unrealized gain on derivatives designated and qualifying as cash flow hedges, net of tax	289				289
Currency translation adjustment	(19,955)				(18,136)		(1,819)
Cash dividends declared - $1.19, $0.98, and $0.83 per share during the year 2015, 2014 and 2013, respectively	(67,986)			(67,986)
Issuance of shares under benefit plans	41,153		33,693			7,460
Issuance of shares under benefit plans (in shares)		787,000
Purchase of shares for treasury	(167,879)					(167,879)
Purchase of shares for treasury (in shares)		(2,722,000)
Equity (Increase) Decrease from Transactions with Noncontrolling Interest Holders	(6,093)		1,702		155		(7,950)
Ending Balance at Dec. 31, 2013	1,530,688	$ 9,858	240,519	1,908,462	(151,941)	(480,296)	4,086
Ending Balance (in shares) at Dec. 31, 2013		81,010,000
Increase (Decrease) in Stockholders' Equity
Net income	253,880			254,686			(806)
Unrecognized amounts from defined benefit pension plans, net of tax	(37,200)				(37,200)
Unrealized gain on derivatives designated and qualifying as cash flow hedges, net of tax	(378)				(378)
Currency translation adjustment	(98,365)				(99,099)		734
Cash dividends declared - $1.19, $0.98, and $0.83 per share during the year 2015, 2014 and 2013, respectively	(76,974)			(76,974)
Issuance of shares under benefit plans	23,578		19,781			3,797
Issuance of shares under benefit plans (in shares)		385,000
Purchase of shares for treasury	(307,178)					(307,178)
Purchase of shares for treasury (in shares)		(4,398,000)
Equity (Increase) Decrease from Transactions with Noncontrolling Interest Holders	(2,270)		(1,484)		(4)		(782)
Ending Balance at Dec. 31, 2014	$ 1,285,781	$ 9,858	258,816	2,086,174	(288,622)	(783,677)	3,232
Ending Balance (in shares) at Dec. 31, 2014	76,997,161	76,997,000
Increase (Decrease) in Stockholders' Equity
Net income	$ 127,412			127,478			(66)
Unrecognized amounts from defined benefit pension plans, net of tax	98,117				98,117
Unrealized gain on derivatives designated and qualifying as cash flow hedges, net of tax	557				557
Currency translation adjustment	(106,935)				(106,312)		(623)
Cash dividends declared - $1.19, $0.98, and $0.83 per share during the year 2015, 2014 and 2013, respectively	(87,814)			(87,814)
Issuance of shares under benefit plans	16,513		14,092			2,421
Issuance of shares under benefit plans (in shares)		274,000
Purchase of shares for treasury	$ (399,494)					(399,494)
Purchase of shares for treasury (in shares)	(6,558,215)	(6,578,000)
Equity (Increase) Decrease from Transactions with Noncontrolling Interest Holders	$ (1,689)				(7)		(1,682)
Ending Balance at Dec. 31, 2015	$ 932,448	$ 9,858	$ 272,908	$ 2,125,838	$ (296,267)	$ (1,180,750)	$ 861
Ending Balance (in shares) at Dec. 31, 2015	70,693,389	70,693,000