Share-Based Compensation (PSUs Vested and Converted) (Details) - PSUs - shares shares in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vested during the year	231	161	85
Award converted during the year, net of shares withheld for taxes	141	96	287
Shares withheld for taxes	90	65	141