XML 65 R54.htm IDEA: XBRL DOCUMENT v3.21.1
Indebtedness - Bank Debt - Additional Information (Detail)
3 Months Ended
Mar. 31, 2021
USD ($)
CommercialBank
Mar. 31, 2020
Dec. 31, 2020
USD ($)
Debt Instrument [Line Items]      
Bank debt $ 116,074,000   $ 693,123,000
Bank Credit Facility      
Debt Instrument [Line Items]      
Bank credit facility, maximum amount 4,000,000,000.0    
Bank credit facility, borrowing base $ 3,000,000,000.0    
Percentage holding of commercial banks, Maximum 7.00%    
Number of commercial banks included in current bank group | CommercialBank 26    
Maturity date of loan Apr. 13, 2023    
Bank commitments $ 2,400,000,000    
Bank debt 124,000,000.0    
Undrawn letters of credit 334,600,000    
Borrowing capacity available under the commitment amount $ 1,900,000,000    
Weighted average interest rate on the bank credit facility 2.20% 3.10%  
Annual rate of commitment fee paid on the undrawn balance 0.30%    
Bank Credit Facility | Alternate Base Rate      
Debt Instrument [Line Items]      
Interest rate margin 0.75%    
Bank Credit Facility | LIBOR Rate      
Debt Instrument [Line Items]      
Interest rate margin 1.75%    
Bank Credit Facility | Minimum      
Debt Instrument [Line Items]      
Annual rate of commitment fee paid on the undrawn balance 0.30%    
Bank Credit Facility | Minimum | Alternate Base Rate      
Debt Instrument [Line Items]      
Base rate on debt 0.25%    
Bank Credit Facility | Minimum | LIBOR Rate      
Debt Instrument [Line Items]      
Base rate on debt 1.25%    
Bank Credit Facility | Maximum      
Debt Instrument [Line Items]      
Annual rate of commitment fee paid on the undrawn balance 0.375%    
Bank Credit Facility | Maximum | Alternate Base Rate      
Debt Instrument [Line Items]      
Base rate on debt 1.25%    
Bank Credit Facility | Maximum | LIBOR Rate      
Debt Instrument [Line Items]      
Base rate on debt 2.25%