Employee Benefits - Expected Return on Plan Assets Narrative (Details)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
U.S.
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Expected return on plan assets, net of administration expenses	7.81%	7.96%	8.80%