Stock Plans (LTIP Target Performance Shares) (Details) - Performance Shares [Member] - shares		3 Months Ended
	Feb. 16, 2017	Mar. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Balance at beginning of period (in shares)		2,859,000
Shares granted (in shares)	2,361,000	2,118,000
Shares earned (in shares)		(617,000)
Shares forfeited (in shares)		(64,000)
Balance at end of period (in shares)		4,296,000