XML 36 R26.htm IDEA: XBRL DOCUMENT
v3.25.2

Components of Net Periodic Benefit Cost (Tables) | 6 Months Ended
--- | ---
Jun. 30, 2025
Components of Net Periodic Benefit Cost |
Schedule of Net Periodic Benefit Costs | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Three Months Ended June 30, | ​ | Six Months Ended June 30,
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | Post-Retirement | ​ | ​ | ​ | ​ | ​ | ​ | ​ | Post-Retirement
​ | ​ | Pension Benefits | ​ | Health Benefits | ​ | Pension Benefits | ​ | Health Benefits
(Dollar amounts in thousands) |  | 2025 |  | 2024 | ​ | 2025 |  | 2024 | ​ | 2025 |  | 2024 | ​ | 2025 |  | 2024
Service cost | ​ | $ | 107 | ​ | $ | 141 | ​ | $ | 3 | ​ | $ | 4 | ​ | $ | 215 | ​ | $ | 282 | ​ | $ | 6 | ​ | $ | 8
Interest cost | ​ |  | 1,017 | ​ |  | 947 | ​ |  | 32 | ​ |  | 35 | ​ |  | 2,033 | ​ |  | 1,894 | ​ |  | 64 | ​ |  | 69
Expected return on plan assets | ​ |  | (1,093) | ​ |  | (1,052) | ​ |  | — | ​ |  | — | ​ |  | (2,187) | ​ |  | (2,103) | ​ |  | — | ​ |  | —
Net amortization of prior service cost | ​ |  | — | ​ |  | — | ​ |  | — | ​ |  | — | ​ |  | — | ​ |  | — | ​ |  | — | ​ |  | —
Net amortization of net (gain) loss | ​ | ​ | — | ​ | ​ | 108 | ​ | ​ | (39) | ​ | ​ | (20) | ​ | ​ | — | ​ | ​ | 217 | ​ | ​ | (78) | ​ | ​ | (40)
Net Periodic Benefit Cost | ​ | $ | 31 | ​ | $ | 144 | ​ | $ | (4) | ​ | $ | 19 | ​ | $ | 61 | ​ | $ | 290 | ​ | $ | (8) | ​ | $ | 37

X
- References No definition available. + Details
Name: | us-gaap_CompensationAndRetirementDisclosureAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of the components of net benefit costs for pension plans and/or other employee benefit plans including service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) recognized due to settlements or curtailments. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Subparagraph (q) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-5 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 715 -SubTopic 20 -Subparagraph (h) -Name Accounting Standards Codification -Paragraph 1 -Section 50 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 + Details
Name: | us-gaap_ScheduleOfNetBenefitCostsTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration