Health Care, Pension and Other Benefits - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Defined Benefit Plan Disclosure [Line Items]
Settlement charge	$ (32,410)
Shares of company stock included in transfer	131,781
Defined Benefit Pension Plans | Domestic Defined Benefit Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Settlement charge	(32,410)
Defined Benefit Pension Plans | Domestic Defined Benefit Pension Plans | Terminated Plan
Defined Benefit Plan Disclosure [Line Items]
Settlement charge	32,400
Defined Benefit Pension Plans | Domestic Defined Benefit Pension Plans | Replacement Plan
Defined Benefit Plan Disclosure [Line Items]
Surplus transferred upon termination and replacement	201,800
Shares of company stock included in transfer	$ 131,800
Shares of company stock included in transfer (in shares)	300,000