Note Pension and postretirement benefits (Components of net periodic postretirement benefit cost) (Detail) - USD ($) $ in Thousands |
3 Months Ended | 6 Months Ended | ||
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Jun. 30, 2017 |
Jun. 30, 2016 |
Jun. 30, 2017 |
Jun. 30, 2016 |
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Pension and Other Postretirement Benefits Disclosure [Line Items] | ||||
Amortization of prior service credit | $ (950) | $ (950) | $ (1,900) | $ (1,900) |
Other Postretirement Benefit Plans Defined Benefit [Member] | ||||
Pension and Other Postretirement Benefits Disclosure [Line Items] | ||||
Service cost | 256 | 289 | 513 | 578 |
Interest cost | 1,426 | 1,505 | 2,851 | 3,010 |
Amortization of prior service credit | (950) | (950) | (1,900) | (1,900) |
Amortization of net loss (gain) | 142 | 275 | 284 | 550 |
Total net periodic pension cost | $ 874 | $ 1,119 | $ 1,748 | $ 2,238 |
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- Definition Pension and Other Postretirement Benefits Disclosure [Line Items] No definition available.
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- Definition Amount included in accumulated other comprehensive income (AOCI) related to gain (loss) expected to be recognized as components of net periodic benefit cost for the fiscal year that follows the most recent annual statement of financial position. No definition available.
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- Definition The increase in a defined benefit pension plan's projected benefit obligation or a defined benefit postretirement plan's accumulated postretirement benefit obligation due to the passage of time. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The total amount of net periodic benefit cost for defined benefit plans for the period. Periodic benefit costs include the following components: service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The actuarial present value of benefits attributed by the pension benefit formula to services rendered by employees during the period. The portion of the expected postretirement benefit obligation attributed to employee service during the period. The service cost component is a portion of the benefit obligation and is unaffected by the funded status of the plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount before tax of reclassification adjustment from accumulated other comprehensive (income) loss for prior service cost (credit) related to pension and other postretirement benefit plans. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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