Comprehensive Income and Accumulated Other Comprehensive Income (Loss) - Summary of Effects of Reclassifications from Accumulated Other Comprehensive Income (Loss) (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2019 USD ($)
Pension and Other Postretirement Benefit Plans
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Total net of tax	$ (219)
Reclassification out of Accumulated Other Comprehensive Income | Actuarial losses
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Total before tax	301
Reclassification out of Accumulated Other Comprehensive Income | Prior service credit
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Total before tax	(14)
Reclassification out of Accumulated Other Comprehensive Income | Pension and Other Postretirement Benefit Plans
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Total before tax	287
Tax benefit	(68)
Total net of tax	$ 219