Employee Benefits - Additional Information (Detail)	0 Months Ended	3 Months Ended
	Jan. 01, 2015	Mar. 31, 2015
Compensation and Retirement Disclosure [Abstract]
Number of consecutive years of employee's compensation		5 years
Number of total years of employee's compensation		10 years
Expected long-term rate of return on plan assets		8.00%
Lump sum death benefit to unmarried beneficiary as percent of accrued benefit payable (percent)	80.00%