Fair Value - Additional Information (Details) - USD ($) |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
|
| Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] | |||
| Impaired loans measured at nonrecurring basis | When the fair value of the collateral is based on an observable market price or a current appraised value, we measure the impaired loan at nonrecurring Level 2. When an appraised value is not available, or management determines the fair value of the collateral is further impaired below the appraised value and there is no observable market price or a discounted cash flow has been used to determine the fair value, we measure the impaired loan at nonrecurring Level 3. | ||
| Real estate owned (“REO”) | $ 2,920,000 | $ 1,734,000 | $ 4,036,000 |
| Fair value mortgage servicing rights | 4,800,000 | 2,200,000 | |
| Fair Value Measurement Level 3 | |||
| Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] | |||
| Total collateral dependent impaired loans | 13,400,000 | 9,000,000 | |
| Reserves related to impaired loans | 0 | 0 | |
| Real estate owned (“REO”) | $ 2,900,000 | $ 1,700,000 | |
| Prepayment rate | 15.00% | ||
| Fair Value Measurement Level 3 | Minimum | |||
| Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] | |||
| Discount rate | 4.00% | ||
| Fair Value Measurement Level 3 | Maximum | |||
| Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] | |||
| Discount rate | 10.00% | ||