Employer Sponsored Benefit Plans - Assumptions Used in Determining the Year-End Benefit Obligation and Annual Net Cost (Details)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Benefit Obligation
Discount rate (as a percent)	3.37%	3.99%
Expected return on plan assets (as a percent)	5.06%	4.08%
Net Cost
Discount rate (as a percent)	3.88%	3.75%	4.21%
Expected return on plan assets (as a percent)	4.65%	5.79%	6.30%