Common Stockholders' Equity (Tables)

12 Months Ended

Dec. 31, 2013

Equity [Abstract]

Weighted Average Number of Common Shares Used In the Computation of Basic and Diluted Earnings per Share

The weighted average number of shares used in the computation of net income per share was as follows:

	2013	2012	2011
Basic	135,304,752	137,097,162	139,687,546
Diluted	140,742,922	143,314,544	145,672,211

Schedule of Changes in Shares of Common Stock Outstanding

Changes in shares of common stock outstanding, net of treasury shares, are presented below. Shares of common stock issued and outstanding do not include shares related to unissued restricted stock units and unexercised stock options.

	2013		2012	2011
Balance, beginning of year	136,017,732		137,520,019	141,009,834
Shares issued	139,790		2,114,168	2,702,303
Shares repurchased	(3,924,355	)	(3,616,455)	(6,192.118)
Balance, end of year	132,233,167		136,017,732	137,520,019