Quarterly report pursuant to Section 13 or 15(d)

Stockholders' Equity (Details Textual)

v3.6.0.2
Stockholders' Equity (Details Textual) - USD ($)
 1 Months Ended 9 Months Ended
Jan. 05, 2017
Jan. 05, 2017
Nov. 30, 2016
Apr. 30, 2012
Class A and Class B [Member] | 2013 Authorization [Member]        
Equity, Class of Treasury Stock [Line Items]        
Repurchase authorization       $ 1,000,000,000.0
Class A and Class B [Member] | 2017 Authorization [Member]        
Equity, Class of Treasury Stock [Line Items]        
Repurchase authorization     $ 1,000,000,000  
Class A Common Stock [Member] | 2013 Authorization [Member]        
Equity, Class of Treasury Stock [Line Items]        
Number of shares repurchased     2,412,193  
Dollar value of shares repurchased     $ 372,600,000  
Class A Common Stock [Member] | 2013 Authorization [Member] | Subsequent Event [Member]        
Equity, Class of Treasury Stock [Line Items]        
Number of shares repurchased 18,670,632 1,988,311    
Dollar value of shares repurchased $ 1,000,000,000 $ 296,900,000    
Class A Common Stock [Member] | 2017 Authorization [Member] | Subsequent Event [Member]        
Equity, Class of Treasury Stock [Line Items]        
Number of shares repurchased 994,142 994,142    
Dollar value of shares repurchased $ 153,100,000 $ 153,100,000