Consolidated Balance Sheets (Parenthetical) (USD $)	Dec. 31, 2013	Dec. 31, 2012
Shareholders' equity:
Common shares, par value	$ 1.25	$ 1.25
Common stock, shares authorized	305,000,000	305,000,000
Common shares, shares issued	176,793,000	176,793,000
Treasury shares, shares	39,630,000	32,389,000