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PENSION PLANS AND OTHER POSTRETIREMENT BENEFITS (Tables) | 3 Months Ended
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Dec. 31, 2016
Pension Plans |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |
Net Periodic Cost | The net periodic pension cost included the following components:
| Three Months Ended December 31,
| 2016 |  | 2015
Spire |  |  |
Service cost – benefits earned during the period | $ | 5.3 |  |  | $ | 3.9 |
Interest cost on projected benefit obligation | 6.9 |  |  | 7.1 |
Expected return on plan assets | (9.9 | ) |  | (8.9 | )
Amortization of prior service cost | 0.2 |  |  | 0.1 |
Amortization of actuarial loss | 3.4 |  |  | 2.0 |
Special termination benefits | — |  |  | 1.6 |
Subtotal | 5.9 |  |  | 5.8 |
Regulatory adjustment | 4.6 |  |  | 5.0 |
Net pension cost | $ | 10.5 |  |  | $ | 10.8 |
Postretirement Plans |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |
Net Periodic Cost | Net periodic postretirement benefit cost for the Company consisted of the following components:
| Three Months Ended December 31,
| 2016 |  | 2015
Spire |  |  |
Service cost – benefits earned during the period | $ | 2.8 |  |  | $ | 2.8 |
Interest cost on accumulated postretirement benefit obligation | 2.1 |  |  | 2.5 |
Expected return on plan assets | (3.4 | ) |  | (3.4 | )
Amortization of prior service credit | — |  |  | 0.1 |
Amortization of actuarial loss | 0.6 |  |  | 0.9 |
Special termination benefit | — |  |  | 2.6 |
Subtotal | 2.1 |  |  | 5.5 |
Regulatory adjustment | (0.8 | ) |  | (4.2 | )
Net postretirement benefit cost | $ | 1.3 |  |  | $ | 1.3 |
Laclede Gas | Pension Plans |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |
Net Periodic Cost |
Laclede Gas |  |  |
Service cost – benefits earned during the period | $ | 3.3 |  |  | $ | 2.5 |
Interest cost on projected benefit obligation | 4.8 |  |  | 5.4 |
Expected return on plan assets | (7.3 | ) |  | (6.7 | )
Amortization of prior service cost | 0.2 |  |  | 0.1 |
Amortization of actuarial loss | 2.9 |  |  | 2.0 |
Special termination benefits | — |  |  | 1.6 |
Subtotal | 3.9 |  |  | 4.9 |
Regulatory adjustment | 2.8 |  |  | 3.5 |
Net pension cost | $ | 6.7 |  |  | $ | 8.4 |
Laclede Gas | Postretirement Plans |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |
Net Periodic Cost |
Laclede Gas |  |  |
Service cost – benefits earned during the period | $ | 2.6 |  |  | $ | 2.7 |
Interest cost on accumulated postretirement benefit obligation | 1.7 |  |  | 2.0 |
Expected return on plan assets | (2.3 | ) |  | (2.1 | )
Amortization of prior service credit | 0.1 |  |  | 0.1 |
Amortization of actuarial loss | 0.6 |  |  | 1.0 |
Special termination benefit | — |  |  | 2.6 |
Subtotal | 2.7 |  |  | 6.3 |
Regulatory adjustment | (0.4 | ) |  | (3.8 | )
Net postretirement benefit cost | $ | 2.3 |  |  | $ | 2.5 |
Alagasco | Pension Plans |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |
Net Periodic Cost |
Alagasco |  |  |
Service cost – benefits earned during the period | $ | 1.6 |  |  | $ | 1.4 |
Interest cost on projected benefit obligation | 1.5 |  |  | 1.7 |
Expected return on plan assets | (1.8 | ) |  | (2.2 | )
Amortization of actuarial loss | 0.5 |  |  | — |
Subtotal | 1.8 |  |  | 0.9 |
Regulatory adjustment | 1.6 |  |  | 1.5 |
Net pension cost | $ | 3.4 |  |  | $ | 2.4 |
Alagasco | Postretirement Plans |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |
Net Periodic Cost |
Alagasco |  |  |
Service cost – benefits earned during the period | $ | 0.1 |  |  | $ | 0.1 |
Interest cost on accumulated postretirement benefit obligation | 0.4 |  |  | 0.5 |
Expected return on plan assets | (1.1 | ) |  | (1.3 | )
Amortization of prior service credit | (0.1 | ) |  | — |
Amortization of actuarial gain | — |  |  | (0.1 | )
Subtotal | (0.7 | ) |  | (0.8 | )
Regulatory adjustment | (0.4 | ) |  | (0.4 | )
Net postretirement benefit income | $ | (1.1 | ) |  | $ | (1.2 | )

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- 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/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + Details
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