Weighted-Average Assumptions Used to Determine Net Periodic Benefit Cost (Detail)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Schedule of Net Periodic Benefit Costs Weighted Average Assumptions [Line Items]
Discount rate	8.65% per annum	9.55% per annum
Long-term rate of compensation increase	11% per annum for first year, 10% for next five years & 7% thereafter	11% per annum for first year, 10% for next five years & 7% thereafter