Quarterly report pursuant to Section 13 or 15(d)

Debt Obligations (Credit Facility - Current Borrowings) - Additional Information (Detail)

v3.7.0.1
Debt Obligations (Credit Facility - Current Borrowings) - Additional Information (Detail) - USD ($)
$ in Thousands
Mar. 31, 2017
Dec. 31, 2016
Line of Credit Facility [Line Items]    
Letters of credit and bank guarantees under the credit facility $ 323,200  
Amount borrowed under the credit facility 417,732 $ 351,341
Credit facility available for revolving loans or issuing new letters of credit 1,070,000  
Letters Of Credit and Bank Guarantees [Member]    
Line of Credit Facility [Line Items]    
Letters of credit and bank guarantees under the credit facility 323,200  
Letters Of Credit and Bank Guarantees [Member] | U S Dollar [Member]    
Line of Credit Facility [Line Items]    
Letters of credit and bank guarantees under the credit facility 223,900  
Letters Of Credit and Bank Guarantees [Member] | Primarily Canadian and Australian dollars [Member]    
Line of Credit Facility [Line Items]    
Letters of credit and bank guarantees under the credit facility 99,300  
Borrowings Under Credit Facility [Member]    
Line of Credit Facility [Line Items]    
Amount borrowed under the credit facility 417,700  
Borrowings Under Credit Facility [Member] | U S Dollar [Member]    
Line of Credit Facility [Line Items]    
Amount borrowed under the credit facility 200,000  
Borrowings Under Credit Facility [Member] | Canadian Dollars [Member]    
Line of Credit Facility [Line Items]    
Amount borrowed under the credit facility $ 217,700