Stockholders' Equity (Narrative) (Details) (USD $) In Thousands, except Share data in Millions, unless otherwise specified	1 Months Ended	3 Months Ended
	Apr. 20, 2012	Mar. 31, 2012 M Y	Mar. 31, 2011	Apr. 17, 2012
Stockholders' Equity [Abstract]
Dividend declared date		Apr. 17, 2012
Dividend declared per share	$ 0.17
Dividends payment date		May 30, 2012
Dividends payable record date		May 02, 2012
Shares granted, approximate	1.2
Option exercise (strike) price per share				$ 54.00
Closing stock price per share on date of grant				$ 49.01
Options vesting and exercisable, maximum		8 years
Options termination period after the end of the relevant vesting period (in months)		13
Total stock-based compensation expense		$ 1,050	$ 900
Total unrecognized compensation expense		$ 13,981
Weighted average period over which total unrecognized compensation expense will be recognized (in years)		4.53