Employee Benefit Plans - Status of Supplemental Executive Retirement Plan (Detail) - Supplemental Employee Retirement Plans, Defined Benefit [Member] - USD ($) $ in Thousands |
12 Months Ended | |
|---|---|---|
Dec. 31, 2017 |
Dec. 31, 2016 |
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| Change in projected benefit obligation: | ||
| Obligation at beginning of year | $ 11,233 | $ 9,234 |
| Service cost | 1,711 | 1,590 |
| Interest cost | 448 | 383 |
| Actuarial loss (gain) | 429 | 295 |
| Benefits paid | (265) | (269) |
| Obligation at end of year | 13,556 | 11,233 |
| Accumulated benefit obligation | 10,204 | 8,557 |
| Change in fair value of plan assets: | ||
| Employer contributions | 265 | 269 |
| Benefits paid | (265) | (269) |
| Funded status recognized | $ (13,556) | $ (11,233) |
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- Definition Amount of actuarial present value of benefits attributed to employee service rendered, excluding assumptions about future compensation level. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of gain (loss) from change in actuarial assumptions which (increases) decreases benefit obligation of defined benefit plan. Assumptions include, but are not limited to, interest, mortality, employee turnover, salary, and temporary deviation from substantive plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of actuarial present value of benefits attributed to service rendered by employee for defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of payment to participant of defined benefit plan which decreases benefit obligation. For pension plan, payment includes, but is not limited to, pension benefits and death benefits. For other postretirement plan, payment includes, but is not limited to, prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available.
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available.
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- Definition Amount of contribution received by defined benefit plan from employer which increases plan assets. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of funded (unfunded) status of defined benefit plan, measured as difference between fair value of plan assets and benefit obligation. Includes, but is not limited to, overfunded (underfunded) status. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of cost recognized for passage of time related to defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of payment to participant under defined benefit plan which decreases plan assets. For pension plan, payment includes, but is not limited to, pension benefits and death benefits. For other postretirement plan, payment includes, but is not limited to, prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of cost for actuarial present value of benefits attributed to service rendered by employee for defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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