Consolidated Statement of Changes in Shareholders' Equity (USD $) In Thousands	Total	Common stock [Member]	Additional paid-in capital [Member]	Retained earnings [Member]	Accumulated other comprehensive income [Member]	Treasury stock [Member]
Balance at Dec. 31, 2012	$ 3,542,612	$ 125,114	$ 1,052,253	$ 2,756,166	$ 295,271	$ (686,192)
Net earnings	292,187			292,187
Other Comprehensive Loss Net Of Tax	(165,269)				(165,269)
Issuance of 291 shares for exercise of options, including tax effect	8,725	291	8,434
Purchase of 1,055 common shares	(42,212)					(42,212)
Stock-based compensation	7,669	18	7,651
Cash dividends declared, $0.555 per share	(55,633)			(55,633)
Balance at Sep. 30, 2013	$ 3,588,079	$ 125,423	$ 1,068,338	$ 2,992,720	$ 130,002	$ (728,404)