Long-Term Stock Incentive Plan - Additional Information (Detail) (USD $)	1 Months Ended
	May 31, 2013
Officers And Key Management Employees [Member] | Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares awarded and issued	80,514
Officers And Key Management Employees [Member] | Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant date fair value	$ 32.87
Third Anniversary Of Grant Date [Member] | Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage of stock options issued	50.00%
Fifth Anniversary Of Grant Date [Member] | Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage of stock options issued	50.00%