XML 90 R77.htm IDEA: XBRL DOCUMENT v3.10.0.1
Loans Held for Sale, at Fair Value - Additional Information (Detail) - USD ($)
3 Months Ended 6 Months Ended
Jun. 30, 2018
Jun. 30, 2017
Jun. 30, 2018
Jun. 30, 2017
Dec. 31, 2017
Accounts Notes And Loans Receivable [Line Items]          
Maximum number of days loans held for sale are typically sold     45 days    
Loans held for sale in nonaccrual status $ 0   $ 0   $ 0
Recognized gain(losses) from change in fair value on loans held for sale (7,800,000) $ (2,200,000) 7,300,000 $ (100,000)  
Interest Income [Member]          
Accounts Notes And Loans Receivable [Line Items]          
Interest income on Loans held for sale 5,000,000 $ 12,700,000 9,700,000 $ 19,200,000  
Greater Than 90 Days Past Due [Member]          
Accounts Notes And Loans Receivable [Line Items]          
Loans held for sale past due $ 0   $ 0   $ 0