Employee Retirement Plans (Tables)

9 Months Ended

Sep. 30, 2019

Employee Retirement Plans [Abstract]

Net Periodic Benefit Expense

	Pension benefits								Postretirement benefits
	Three months ended				Nine months ended				Three months ended				Nine months ended
	September 30,				September 30,				September 30,				September 30,
	2019		2018		2019		2018		2019		2018		2019		2018
Service cost	$	25	$	26	$	76	$	77	$	3	$	3	$	7	$	9
Interest cost		37		32		111		97		7		6		21		18
Expected return on plan assets		(42)		(47)		(128)		(142)
Amortization of actuarial net gain										(1)				(1)
Amortization of prior service ‎   cost (credit)		2		2		5		6		(2)		(2)		(6)		(5)
Recognition of actuarial loss						23		1
Total pension and postretirement ‎   benefit expense	$	22	$	13	$	87	$	39	$	7	$	7	$	21	$	22