Stock Plans (LTIP Target Performance Shares) (Details) (Performance Shares [Member])	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Balance at beginning of period (in shares)	1,749,000	979,000
Shares granted (in shares)	1,037,000	1,124,000	979,000
Shares forfeited (in shares)	(104,000)	(354,000)
Balance at end of period (in shares)	2,682,000	1,749,000	979,000