XML 214 R177.htm IDEA: XBRL DOCUMENT v3.19.1
Guarantor Statements - Additional Information (Detail) - USD ($)
$ in Billions
12 Months Ended
Dec. 31, 2018
Dec. 31, 2017
Dec. 31, 2016
Notes [member]      
Supplemental Guarantor Information [line items]      
Borrowings outstanding amount $ 12.5 $ 8.9 $ 6.3
Notes [member] | Bottom of range [member]      
Supplemental Guarantor Information [line items]      
Interest rate of borrowings 1.375%    
Notes [member] | Top of range [member]      
Supplemental Guarantor Information [line items]      
Interest rate of borrowings 5.90%    
UCC and UNUS [member]      
Supplemental Guarantor Information [line items]      
Ownership percentage 100.00%