Stock Plans (LTIP Target Performance Shares) (Details) (Performance Shares [Member])	9 Months Ended
	Sep. 30, 2013
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Balance at beginning of period (in shares)	979,000
Shares granted (in shares)	1,124,000
Shares forfeited (in shares)	(338,000)
Balance at end of period (in shares)	1,765,000