XML 86 R72.htm IDEA: XBRL DOCUMENT v3.3.1.900
Deferred Compensation - Additional information (Detail) - USD ($)
shares in Millions
3 Months Ended 12 Months Ended
Mar. 31, 2015
Mar. 31, 2014
Jun. 30, 2013
Mar. 31, 2013
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Investments And Employee Deferred Compensation Plan [Line Items]              
Deferred Equity Participation Plan, distributions to key executives, age         Age 62 (or the one-year anniversary of the date of the grant for participants over the age of 61 as of the grant date) or upon or after their actual retirement    
Age 62 Plan [Member]              
Investments And Employee Deferred Compensation Plan [Line Items]              
Awards approved by committee, value $ 8,900,000 $ 9,200,000   $ 8,000,000      
Charge to compensation expenses related to awards         $ 7,200,000 $ 7,400,000 $ 7,200,000
Common stock purchased from open market, share     1.2        
Common stock purchased from open market, value     $ 52,400,000        
Unearned deferred compensation, value         $ 33,500,000 $ 28,200,000  
Unearned deferred compensation, shares         2.1 1.9  
Total intrinsic value of unvested equity based awards         $ 85,200,000 $ 89,100,000  
Cash and equity awards with aggregate fair value vested and distributed to participants         2,300,000 18,800,000 $ 1,400,000
Deferred Cash Participation Plan (DCPP) [Member]              
Investments And Employee Deferred Compensation Plan [Line Items]              
Awards approved by committee, value $ 2,700,000 $ 2,900,000          
Charge to compensation expenses related to awards         1,100,000 2,800,000  
Cash and equity awards with aggregate fair value vested and distributed to participants         $ 0 $ 100,000