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Share-based Compensation (Additional Information) (Details)
1 Months Ended 3 Months Ended 12 Months Ended
Aug. 31, 2014
shares
Mar. 31, 2017
USD ($)
unit / shares
fungible_unit
$ / shares
shares
Mar. 31, 2016
USD ($)
shares
Dec. 31, 2016
USD ($)
shares
Dec. 31, 2015
shares
Jan. 01, 2008
shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Capitalized to assets associated with compensation expense related to our long-term compensation plans, restricted stock and stock options   $ 1,600,000 $ 1,500,000      
Stock options            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Period of commencement of option vesting, from date of grant (in years)   1 year        
Exercise price of options granted, low end of the range (in dollars per share) | $ / shares   $ 20.67        
Exercise price of options granted, high end of the range (in dollars per share) | $ / shares   $ 137.18        
Remaining weighted average contractual life of the options outstanding (in years)   3 years 8 months        
Remaining average contractual life of the options exercisable (in years)   2 years 9 months        
Total unrecognized compensation cost related to unvested stock awards   $ 12,600,000        
Weighted average period for recognition of compensation cost related to unvested stock awards (in years)   2 years        
Weighted average fair value of options granted during the period   $ 1,496,838   $ 8,363,036    
Stock options | Minimum            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Award expiration period (in years)   5 years        
Options vesting period (in years)   1 year        
Stock options | Maximum            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Award expiration period (in years)   10 years        
Options vesting period (in years)   5 years        
Restricted Stock Awards            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Compensation expense   $ 2,380,926 7,153,966      
Total unrecognized compensation cost related to unvested stock awards   $ 18,400,000        
Weighted average period for recognition of compensation cost related to unvested stock awards (in years)   2 years 1 month        
Annual award vesting rate, low end of range (as a percent)   15.00%        
Annual award vesting rate, high end of range (as a percent)   35.00%        
Fair value of restricted stock vested during the period   $ 8,000,000   $ 7,600,000    
Weighted average fair value of options granted during the period   $ 0 $ 10,650,077      
Awards granted (in shares) | shares   0 98,800      
Awards outstanding (in shares) | shares   3,202,031   3,202,031 3,137,881  
LTIP units            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Weighted average fair value of options granted during the period   $ 20,500,000   $ 25,400,000    
Performance Shares [Member]            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Total unrecognized compensation cost related to unvested stock awards   $ 12,100,000        
Weighted average period for recognition of compensation cost related to unvested stock awards (in years)   1 year 5 months        
Share-based Compensation   $ 10,000,000 $ 9,500,000      
Third Amendment and Restated 2005 Stock Option and Incentive Plan            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Maximum fungible units that may be granted (in shares) | fungible_unit   27,030,000        
Fungible units per share (in fungible units per share) | unit / shares   3.74        
Shares that may be issued if equal to fungible units (shares) (less than) | shares   27,030,000        
Fungible units | fungible_unit   8,700,000        
Third Amendment and Restated 2005 Stock Option and Incentive Plan | Stock options            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Compensation expense   $ 0 2,000,000      
Stock options, stock appreciation rights and other awards            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Fungible units per share (in fungible units per share) | unit / shares   0.73        
Award expiration period (in years)   5 years        
All other awards            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Fungible units per share (in fungible units per share) | unit / shares   1        
Award expiration period (in years)   10 years        
Long Term Outperformance Compensation Program 2014 [Member]            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Compensation expense   $ 2,100,000 1,500,000      
Capitalized to assets associated with compensation expense related to our long-term compensation plans, restricted stock and stock options   29,200,000        
LTIP units earned (in shares) | shares 610,000          
Performance period (in years) 3 years          
Award period (in years) 3 years          
Long Term Outperformance Compensation Program 2014 [Member] | Vesting on August 31, 2017            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Percentage of units vested 50.00%          
Long Term Outperformance Compensation Program 2014 [Member] | Vesting on August 31, 2018            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Percentage of units vested 50.00%          
Deferred Stock Compensation Plan for Directors            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Compensation expense   $ 1,900,000 $ 1,600,000      
Maximum percentage of the annual retainer fee, chairman fees and meeting fees that may be deferred by non-employee directors (percent)   100.00%        
Awards granted (in shares) | shares   9,320        
Shares issued (in shares) | shares   8,592        
Awards outstanding (in shares) | shares   96,447        
Employee Stock Purchase Plan            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Shares of common stock available for issuance (shares) | shares           500,000
Duration of each offering period starting the first day of each calendar quarter (in months)   3 months        
Share Based Compensation Arrangement by Share Based Payment Award, Purchase Price as Percentage of Market Value of Common Stock   85.00%        
Shares of common stock issued (shares) | shares   97,446