Shareholders' Equity - Reconciliation of Basic and Diluted Weighted Average Shares Outstanding (Detail) - shares	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Equity [Abstract]
Basic weighted average shares outstanding	125,094,628	130,721,738	137,646,885
Weighted average dilutive options outstanding	1,662,607	1,918,506	1,916,900
Diluted weighted average shares outstanding	126,757,235	132,640,244	139,563,785