Quarterly report pursuant to Section 13 or 15(d)

Income Taxes - Additional Information (Detail)

v3.10.0.1
Income Taxes - Additional Information (Detail) - USD ($)
$ in Thousands
3 Months Ended 9 Months Ended 12 Months Ended
Dec. 31, 2018
Mar. 31, 2018
Sep. 30, 2018
Dec. 31, 2018
Dec. 31, 2017
Sep. 30, 2017
Dec. 31, 2016
Schedule Of Income Taxes [Line Items]              
U.S. federal and state statutory rate     26.00%        
Provisional tax   $ 89,000     $ 99,900    
Reduction in provisional tax     $ 10,900        
Cash and cash equivalents     802,771   $ 736,431 $ 802,932 $ 718,536
Non-US [Member]              
Schedule Of Income Taxes [Line Items]              
Cash and cash equivalents     $ 405,000        
Non-US [Member] | Geographic concentration risk [Member] | Cash and Cash Equivalents Geographical Area [Member]              
Schedule Of Income Taxes [Line Items]              
Percentage of cash and cash equivalents     50.50%        
Non-US [Member] | Funds Available For Repatriation [Member]              
Schedule Of Income Taxes [Line Items]              
Cash and cash equivalents     $ 235,300        
Minimum [Member] | Non-U.S jurisdictions [Member]              
Schedule Of Income Taxes [Line Items]              
Statutory federal rate     0.00%        
Minimum [Member] | Scenario Forecast [Member]              
Schedule Of Income Taxes [Line Items]              
Effective tax rate, remainder of fiscal year 17.00%     13.00%      
Maximum [Member] | Non-U.S jurisdictions [Member]              
Schedule Of Income Taxes [Line Items]              
Statutory federal rate     34.00%        
Maximum [Member] | Scenario Forecast [Member]              
Schedule Of Income Taxes [Line Items]              
Effective tax rate, remainder of fiscal year 20.00%     15.00%