XML 124 R110.htm IDEA: XBRL DOCUMENT v3.3.1.900
Stock-Based Compensation - Summary of Share Option Activity of Stock Option and Stock Appreciation Rights Under 2001 Plan (Detail) - 2001 Plan [Member] - $ / shares
12 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Stock Option [Member]      
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]      
Stock based compensation, Shares Outstanding, beginning balance 35,300 53,800 80,800
Stock based compensation, Shares, Exercised (3,300) (18,500) (11,600)
Stock based compensation, Shares, Forfeited (14,000)   (15,400)
Stock based compensation, Shares Outstanding, ending balance 18,000 35,300 53,800
Stock based compensation, Shares, Exercisable 18,000    
Stock based compensation, Weighted Average Fair Value, beginning balance $ 62.47 $ 53.99 $ 52.43
Stock based compensation, Weighted Average Fair Value, Exercised 33.16 37.80 30.39
Stock based compensation, Weighted Average Fair Value Per Share, Forfeited 66.54   63.58
Stock based compensation, Weighted Average Fair Value, ending balance 64.69 $ 62.47 $ 53.99
Stock based compensation, Weighted Average Fair Value, Exercisable $ 64.69    
Stock based compensation, Weighted Average Remaining Contractual Term, Outstanding 1 year 4 months 6 days    
Stock based compensation, Weighted Average Remaining Contractual Term, Exercisable 1 year 4 months 6 days    
Stock Appreciation Rights [Member]      
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]      
Stock based compensation, Shares Outstanding, beginning balance 35,300 53,800 80,800
Stock based compensation, Shares, Exercised (3,300) (18,500) (11,600)
Stock based compensation, Shares, Forfeited (14,000)   (15,400)
Stock based compensation, Shares Outstanding, ending balance 18,000 35,300 53,800
Stock based compensation, Shares, Exercisable 18,000    
Stock based compensation, Weighted Average Fair Value, beginning balance $ 5.56 $ 1.61 $ 1.12
Stock based compensation, Weighted Average Fair Value, Exercised 12.19 11.20 4.29
Stock based compensation, Weighted Average Fair Value Per Share, Forfeited 4.84   0.46
Stock based compensation, Weighted Average Fair Value, ending balance 2.64 $ 5.56 $ 1.61
Stock based compensation, Weighted Average Fair Value, Exercisable $ 2.64    
Stock based compensation, Weighted Average Remaining Contractual Term, Outstanding 1 year 4 months 6 days    
Stock based compensation, Weighted Average Remaining Contractual Term, Exercisable 1 year 4 months 6 days