Plan Assumptions (Detail)		12 Months Ended
		Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
For measuring benefit obligations at year end
Discount rate		4.16%	3.82%	4.72%
Rate of compensation increase	[1]			4.00%
Expected return on plan assets		7.00%	7.25%	7.50%
For measuring net periodic benefit cost
Discount rate		3.82%	4.72%	3.83%
Rate of compensation increase	[1]			4.00%
Expected return on plan assets		7.00%	7.25%	7.50%

[1] Since the Plan’s benefits were frozen, except for grandfathered employees, the rate of compensation increase is no longer applicable beginning in 2014 since minimal grandfathered employees are still accruing benefits.