Employee Benefit Plans (Combined Activity in Corporations Defined Benefit Pension Plans) (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Compensation and Retirement Disclosure [Abstract]
Benefit obligation at beginning of year	$ 178,158	$ 157,855	$ 145,246
Interest cost	7,341	7,801	7,892
Actuarial (gain) loss	(15,333)	18,436	10,383
Benefits paid	(6,290)	(5,934)	(5,666)
Benefit obligation at end of year	163,876	178,158	157,855
Fair value of plan assets at beginning of year	145,901	137,253	141,050
Actual return on plan assets	24,489	13,931	(3,776)
Employer contributions	669	651	5,645
Benefits paid	(6,290)	(5,934)	(5,666)
Fair value of plan assets at end of year	164,769	145,901	137,253
Funded status of the plan at end of year and accrued (benefit) liability recognized	(893)	32,257	20,602
Accumulated benefit obligation at end of year	$ 163,876	$ 178,158	$ 157,855