Shareholders' Equity - Common Stock Activity (Detail)								12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2013 Common Stock [Member]	Dec. 31, 2012 Common Stock [Member]	Dec. 31, 2011 Common Stock [Member]	Dec. 31, 2010 Common Stock [Member]	Dec. 31, 2013 Treasury Stock, at Cost [Member]	Dec. 31, 2012 Treasury Stock, at Cost [Member]	Dec. 31, 2011 Treasury Stock, at Cost [Member]
Balance, beginning of year				371,980,460	371,980,460	371,980,460	371,980,460	110,217,445	99,519,509	74,707,547
Repurchase of shares								14,887,701	13,094,640	27,582,889
Share activity under stock-based employee compensation plans								(1,431,177)	(2,396,704)	(2,770,927)
Balance, end of year				371,980,460	371,980,460	371,980,460	371,980,460	123,673,969	110,217,445	99,519,509
Common stock outstanding, end of year	248,306,491	261,763,015	272,460,951