Restructuring (Narrative) (Details) - employee	3 Months Ended
	Jun. 30, 2020	Dec. 31, 2019	Dec. 31, 2017
2020 Repositioning Actions
Restructuring Cost and Reserve [Line Items]
Restructuring and related cost, expected number of positions eliminated	1,200
Restructuring and related cost, number of positions eliminated, period percent	11.00%
2019 Repositioning Actions
Restructuring Cost and Reserve [Line Items]
Restructuring and related cost, expected number of positions eliminated		180
Restructuring and related cost, number of positions eliminated, period percent		1.00%
2017 Repositioning Actions
Restructuring Cost and Reserve [Line Items]
Restructuring and related cost, expected number of positions eliminated			300
Restructuring and related cost, number of positions eliminated, period percent			3.00%