Employee Benefit Plans (Net Periodic Benefit Cost (Benefit)) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Retirement Benefits [Abstract]
Expected return on plan assets, net of expenses	$ (11,916)	$ (11,117)	$ (11,558)
Interest cost on projected benefit obligation	5,898	6,189	6,958
Net amortization and deferral	5,002	5,429	6,247
SERP settlement costs	0	0	1,027
Net periodic expense (benefit)	$ (1,016)	$ 501	$ 2,674