Unaudited Condensed Consolidated Statement of Equity Statement (USD $) In Thousands, unless otherwise specified	Total	Common Stock	Treasury Stock	Capital in Excess of Par Value	Accumulated Deficit	Accumulated Other Comprehensive Income	Noncontrolling Interests
Balance at beginning of period at Dec. 31, 2012	$ 1,362,827	$ 211,057	$ (10)	$ 1,307,058	$ (286,795)	$ 111,717	$ 19,800
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Comprehensive income	53,206	0	0	0	57,620	(5,512)	1,098
Dividends declared on common stock	(12,698)	0	0	(12,698)	0	0	0
Employee share-based compensation earned	2,830	0	0	2,830	0	0	0
Stock option exercises	3,094	350	0	2,744	0	0	0
Tax Benefits Related to Share-Based Awards	772	0	0	772	0	0	0
Restricted stock awards, net of forfeitures	0	378	(3)	(375)	0	0	0
Purchase of Company common stock	(1,708)	0	(109)	(676)	(923)	0	0
Purchase of noncontrolling interest	(8,333)	0	0	(1,696)	0	0	(6,637)
Noncontrolling interest payment	(900)	0	0	0	0	0	(900)
Other	(9)	1	0	(10)	0	0	0
Balance at end of period at Mar. 31, 2013	1,399,081	211,786	(122)	1,297,949	(230,098)	106,205	13,361
Balance at beginning of period at Dec. 31, 2013	1,424,378	212,327	(10)	1,259,348	(145,876)	88,441	10,148
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Comprehensive income	30,191	0	0	0	41,102	(11,226)	315
Dividends declared on common stock	(17,080)	0	0	(17,080)	0	0	0
Employee share-based compensation earned	3,130	0	0	3,130	0	0	0
Stock option exercises	8,676	964	0	7,712	0	0	0
Tax Benefits Related to Share-Based Awards	6,743	0	0	6,743	0	0	0
Restricted stock awards, net of forfeitures	0	344	0	(344)	0	0	0
Purchase of Company common stock	(1,814)	0	(106)	(589)	(1,119)	0	0
Purchase of noncontrolling interest	(15,000)	0	0	(7,441)	0	0	(7,559)
Noncontrolling interest payment	(135)	0	0	0	0	0	(135)
Retirement of treasury shares	0	(42)	(42)	0	0	0	0
Other	107	13	0	94	0	0	0
Balance at end of period at Mar. 31, 2014	$ 1,439,196	$ 213,606	$ (74)	$ 1,251,573	$ (105,893)	$ 77,215	$ 2,769