Fair Value Measurement - Reconciliation of Assets and Liabilities Measured at Fair Value Using Significant Unobservable Inputs (Level 3) on Recurring Basis (Detail) - Mortgage Servicing Rights [Member] - USD ($) $ in Thousands |
3 Months Ended | 6 Months Ended | ||
---|---|---|---|---|
Jun. 30, 2018 |
Jun. 30, 2017 |
Jun. 30, 2018 |
Jun. 30, 2017 |
|
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] | ||||
Beginning Balance | $ 6,953 | $ 6,860 | $ 6,687 | $ 6,595 |
Transfers into (out of) Level 3 | 0 | 0 | 0 | 0 |
Change Included in Earnings | (36) | (457) | 75 | (470) |
Issuances | 104 | 193 | 259 | 471 |
Ending Balance | $ 7,021 | $ 6,596 | $ 7,021 | $ 6,596 |