Accumulated Other Comprehensive Loss - Reclassifications from accumulated other comprehensive loss (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other (income) expense, net	$ (1,633)	$ 1,102
Total before tax	660,461	(25,507)
Tax benefit	(27,006)	5,569
Net income	633,455	(19,938)
Accumulated Defined Benefit Plans Adjustment, Net Gain (Loss) And Net Transition Including Portion Attributable to Noncontrolling Interest | Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other (income) expense, net	132	91
Accumulated Defined Benefit Plans Adjustment, Settlement Gain (Loss) Including Portion Attributable to Noncontrolling Interest | Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other (income) expense, net		486
Accumulated Defined Benefit Plans Adjustment Including Portion Attributable to Noncontrolling Interest | Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Total before tax	132	577
Tax benefit	(33)	(155)
Net income	$ 99	$ 422