Quarterly report pursuant to Section 13 or 15(d)

Accumulated Other Comprehensive Income - Additional Information (Detail)

v3.19.1
Accumulated Other Comprehensive Income - Additional Information (Detail) - USD ($)
$ in Thousands
3 Months Ended
Jan. 01, 2018
Mar. 31, 2019
Mar. 31, 2018
Accumulated Other Comprehensive Income [Line Items]      
Net gain (loss) on sales of securities   $ 725 $ (428)
Net unrealized gains (losses) recorded in comprehensive income   (206)  
Unrealized Gains and Losses on Available for Sale Securities      
Accumulated Other Comprehensive Income [Line Items]      
Reduction of unrealized losses related to securities $ 529    
Accumulated Other Comprehensive Income (Loss)      
Accumulated Other Comprehensive Income [Line Items]      
Adjustment to accumulated other comprehensive income related to adoption of ASU 2016-01 and 2018-02, net of tax 17    
Tax Benefit (Expense)      
Accumulated Other Comprehensive Income [Line Items]      
Reduction in tax benefits upon adoption of ASUs $ 546    
Reclassification out of Accumulated Other Comprehensive Income [Member] | Unrealized Gains and Losses on Available for Sale Securities      
Accumulated Other Comprehensive Income [Line Items]      
Net gain (loss) on sales of securities   $ 725