Employee Benefit Plans (Net Periodic Costs) (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Defined Benefit Plan Net Periodic Benefit Cost [Abstract]
Service costs	$ 70	$ 130	$ 211	$ 390
Interest costs	2,280	2,018	6,838	6,054
Amortization of net actuarial loss	916	1,205	2,746	3,615
Amortization of prior service credit	(1,018)	(1,045)	(3,053)	(3,135)
Net periodic costs	$ 2,248	$ 2,308	$ 6,742	$ 6,924