Spire Alabama 10-Q 6 Feb 19 2019 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Dec. 31, 2018	Feb. 04, 2019
Entity Information [Line Items]
Entity Registrant Name	SPIRE INC
Entity Central Index Key	1,126,956
Current Fiscal Year End Date	--09-30
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Common Stock, Shares Outstanding (in shares)		50,740,277
Document Fiscal Year Focus	2,019
Document Fiscal Period Focus	Q1
Trading Symbol	SR
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Dec. 31, 2018
Spire Missouri Inc
Entity Information [Line Items]
Entity Registrant Name	SPIRE MISSOURI INC
Entity Central Index Key	57,183
Current Fiscal Year End Date	--09-30
Entity Current Reporting Status	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Common Stock, Shares Outstanding (in shares)		24,577
Document Fiscal Year Focus	2,019
Document Fiscal Period Focus	Q1
Trading Symbol	SR
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Dec. 31, 2018
Spire Alabama Inc
Entity Information [Line Items]
Entity Registrant Name	SPIRE ALABAMA INC
Entity Central Index Key	3,146
Current Fiscal Year End Date	--09-30
Entity Current Reporting Status	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Common Stock, Shares Outstanding (in shares)		1,972,052
Document Fiscal Year Focus	2,019
Document Fiscal Period Focus	Q1
Trading Symbol	SR
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Dec. 31, 2018

CONDENSED CONSOLIDATED STATEMEN

CONDENSED CONSOLIDATED STATEMENTS OF INCOME (UNAUDITED) - USD ($) shares in Millions, $ in Millions	3 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Operating Revenues:
Gas Utility	$ 573.8	$ 541.9
Gas Marketing and other	28.2	19.9
Total Operating Revenues	602	561.8
Gas Utility
Natural and propane gas	251.7	240.8
Other operation and maintenance expenses	102.5	99
Depreciation and amortization	43.7	40.3
Taxes, other than income taxes	39.2	36.7
Total Gas Utility Operating Expenses	437.1	416.8
Gas Marketing and other	59.8	41
Total Operating Expenses	496.9	457.8
Operating Income	105.1	104
Other Income, Net	2.8	3.3
Interest Charges:
Interest on long-term debt	20.4	20.7
Other interest charges	5.5	3.7
Total Interest Charges	25.9	24.4
Income Before Income Taxes	82	82.9
Income Tax Expense (Benefit)	14.7	(33.1)
Net Income (Loss)	$ 67.3	$ 116
Weighted Average Number of Shares Outstanding:
Basic	50.6	48.2
Diluted	50.8	48.4
Basic Earnings Per Share	$ 1.33	$ 2.40
Diluted Earnings Per Share	$ 1.32	$ 2.39
Spire Alabama
Operating Revenues:
Gas Utility	$ 133.5	$ 120.8
Total Operating Revenues	133.5	120.8
Gas Utility
Natural and propane gas	59.5	49
Other operation and maintenance expenses	34.4	32.8
Depreciation and amortization	13.6	12.8
Taxes, other than income taxes	8.9	8.2
Total Operating Expenses	116.4	102.8
Operating Income	17.1	18
Other Income, Net	1.8	1.4
Interest Charges:
Interest on long-term debt	3.6	2.9
Other interest charges	1.5	1.1
Total Interest Charges	5.1	4
Income Before Income Taxes	13.8	15.4
Income Tax Expense (Benefit)	3.5	65
Net Income (Loss)	$ 10.3	$ (49.6)

CONDENSED CONSOLIDATED STATEM_2

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Net Income	$ 67.3	$ 116
Cash flow hedging derivative instruments:
Net hedging (loss) gain arising during the period	(10.4)	0.1
Reclassification adjustment for income included in net income	(0.3)	(0.4)
Net unrealized loss on cash flow hedging derivative instruments	(10.7)	(0.3)
Net gain on defined benefit pension and other postretirement plans		0.1
Net unrealized loss on available for sale securities		(0.1)
Other Comprehensive Loss, Before Tax	(10.7)	(0.3)
Income Tax Benefit Related to Items of Other Comprehensive Loss	(2.5)	(0.1)
Other Comprehensive Loss, Net of Tax	(8.2)	(0.2)
Comprehensive Income	59.1	115.8
Operating Revenues:
Gas Utility	573.8	541.9
Total Operating Revenues	602	561.8
Gas Utility
Natural and propane gas	251.7	240.8
Other operation and maintenance expenses	102.5	99
Depreciation and amortization	43.7	40.3
Taxes, other than income taxes	39.2	36.7
Total Operating Expenses	496.9	457.8
Operating Income	105.1	104
Other (Expense) Income, Net	2.8	3.3
Interest Charges:
Interest on long-term debt	20.4	20.7
Other interest charges	5.5	3.7
Total Interest Charges	25.9	24.4
Income Before Income Taxes	82	82.9
Income Tax Expense (Benefit)	14.7	(33.1)
Net Income (Loss)	67.3	116
Spire Missouri
Net Income	51.2	89.4
Operating Revenues:
Gas Utility	413.2	392.3
Total Operating Revenues	413.2	392.3
Gas Utility
Natural and propane gas	223.4	206.2
Other operation and maintenance expenses	63.1	60.1
Depreciation and amortization	27.2	24.8
Taxes, other than income taxes	28.1	26.2
Total Operating Expenses	341.8	317.3
Operating Income	71.4	75
Other (Expense) Income, Net	(0.7)	1
Interest Charges:
Interest on long-term debt	9.4	9.9
Other interest charges	2.7	1.7
Total Interest Charges	12.1	11.6
Income Before Income Taxes	58.6	64.4
Income Tax Expense (Benefit)	7.4	(25)
Net Income (Loss)	$ 51.2	$ 89.4

CONDENSED CONSOLIDATED BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS (UNAUDITED) - USD ($) $ in Millions	Dec. 31, 2018	Sep. 30, 2018	Dec. 31, 2017
ASSETS
Utility Plant	$ 5,754.8	$ 5,653.3	$ 5,351.7
Less: Accumulated depreciation and amortization	1,709.5	1,682.8	1,641
Net Utility Plant	4,045.3	3,970.5	3,710.7
Non-utility Property (net of accumulated depreciation and amortization of $11.1, $10.4 and $8.6 at December 31, 2018, September 30, 2018, and December 31, 2017, respectively)	254.5	174.5	105.3
Goodwill	1,171.6	1,171.6	1,171.6
Other Investments	69.5	68.7	66.3
Total Other Property and Investments	1,495.6	1,414.8	1,343.2
Current Assets:
Cash and cash equivalents	8.4	4.4	6.7
Accounts receivable:
Utility	339.2	151.9	333.6
Other	242.1	167.3	135.3
Allowance for doubtful accounts	(24.6)	(22.4)	(21.3)
Delayed customer billings	10.9	6.9	7.5
Inventories:
Natural gas	176.2	175.2	171.6
Propane gas	12	12	12
Materials and supplies	24.5	23.1	21.3
Natural gas receivable	2.2	1.8	3.5
Derivative instrument assets	19.7	13.3	4.7
Unamortized purchased gas adjustments	3	8.2	77.9
Other regulatory assets	60.4	64.6	71.4
Prepayments	25.7	31	24.6
Other	5.6	22.3	3.7
Total Current Assets	905.3	659.6	852.5
Deferred Charges and Other Assets:
Regulatory assets	655.1	669.8	716.6
Other	130.9	128.9	78.1
Total Deferred Charges and Other Assets	786	798.7	794.7
Total Assets	7,232.2	6,843.6	6,701.1
Capitalization:
Common stock (par value $1.00 per share; 70.0 million shares authorized; 50.7 million, 50.7 million and 48.3 million shares issued and outstanding at December 31, 2018, September 30, 2018 and December 31, 2017, respectively)	50.7	50.7	48.3
Paid-in capital and common stock	1,482.8	1,482.7	1,324.9
Retained earnings	752.9	715.6	703
Accumulated other comprehensive (loss) income	(1.8)	6.4	3
Total Shareholders' Equity	2,284.6	2,255.4	2,079.2
Redeemable noncontrolling interest	0	7.9	6.5
Long-term debt (less current portion)	1,992	1,900.1	2,030
Total Capitalization	4,276.6	4,163.4	4,115.7
Current Liabilities:
Current portion of long-term debt	175	175.5	105.5
Notes payable	626.1	553.6	583.6
Accounts payable	430.9	290.1	245.6
Advance customer billings	19.8	22.7	27.3
Wages and compensation accrued	32.8	39.7	29.6
Dividends payable	31.3	30	28.1
Customer deposits	36.1	35.5	35.9
Interest accrued	27.2	15.2	26.3
Taxes accrued	44.6	65.4	36
Unamortized purchased gas adjustments	6.1	2.9	1
Other regulatory liabilities	30.9	32.8	20.5
Other	102.6	58.3	71.9
Total Current Liabilities	1,563.4	1,321.7	1,211.3
Deferred Credits and Other Liabilities:
Deferred income taxes	453.2	435.8	441
Pension and postretirement benefit costs	182.1	180.2	233.6
Asset retirement obligations	324.5	321.1	299.7
Regulatory liabilities	363.4	354.6	335.1
Other	69	66.8	64.7
Total Deferred Credits and Other Liabilities	1,392.2	1,358.5	1,374.1
Commitments and Contingencies (Note 11)
Total Capitalization and Liabilities	7,232.2	6,843.6	6,701.1
Spire Missouri
ASSETS
Utility Plant	3,395.8	3,331	3,141.2
Less: Accumulated depreciation and amortization	720.4	705.8	696.1
Net Utility Plant	2,675.4	2,625.2	2,445.1
Goodwill	210.2	210.2	210.2
Other Investments	53.6	55	60.1
Total Other Property and Investments	263.8	265.2	270.3
Current Assets:
Cash and cash equivalents	4.9	2	4.1
Accounts receivable:
Utility	227.4	103.9	238.3
Associated companies	4.7	2.7	7.3
Other	17.7	16.6	20
Allowance for doubtful accounts	(18.1)	(16)	(16.8)
Delayed customer billings	10.9	6.9	7.5
Inventories:
Natural gas	129.3	127.9	127.1
Propane gas	12	12	12
Materials and supplies	14.3	13.2	12.5
Unamortized purchased gas adjustments	0	1	38.5
Other regulatory assets	29.7	29.7	38.2
Prepayments	14.7	19.1	15.6
Total Current Assets	447.5	319	504.3
Deferred Charges and Other Assets:
Regulatory assets	427.6	441.1	484.1
Other	51.9	50.8	5.6
Total Deferred Charges and Other Assets	479.5	491.9	489.7
Total Assets	3,866.2	3,701.3	3,709.4
Capitalization:
Paid-in capital and common stock	761.6	760.4	757.3
Retained earnings	542.5	501.1	492.4
Accumulated other comprehensive (loss) income	(1.6)	(1.6)	(1.7)
Total Shareholders' Equity	1,302.5	1,259.9	1,248
Long-term debt (less current portion)	924.5	824.4	874.1
Total Capitalization	2,227	2,084.3	2,122.1
Current Liabilities:
Current portion of long-term debt	50	50	100
Notes payable – associated companies	308	345.3	275.6
Accounts payable	101.5	81.7	73.5
Accounts payable – associated companies	17.4	5.8	8.9
Advance customer billings	9.1	9.5	10.5
Wages and compensation accrued	25.3	31.3	22.9
Dividends payable	0	9	13.5
Customer deposits	13.3	13.1	13.4
Interest accrued	11.2	7.8	11.6
Taxes accrued	14.6	32	12.3
Unamortized purchased gas adjustments	5.8	1.9	0
Other regulatory liabilities	14.8	14.8	2.7
Other	54.5	20.1	48.4
Total Current Liabilities	625.5	622.3	593.3
Deferred Credits and Other Liabilities:
Deferred income taxes	373.7	361	382.2
Pension and postretirement benefit costs	137.7	136.9	167.8
Asset retirement obligations	175.9	174.1	160.3
Regulatory liabilities	279.7	274.9	241.2
Other	46.7	47.8	42.5
Total Deferred Credits and Other Liabilities	1,013.7	994.7	994
Commitments and Contingencies (Note 11)
Total Capitalization and Liabilities	3,866.2	3,701.3	3,709.4
Spire Alabama
ASSETS
Utility Plant	1,994.5	1,964.3	1,858.5
Less: Accumulated depreciation and amortization	841.4	830.2	791.7
Net Utility Plant	1,153.1	1,134.1	1,066.8
Current Assets:
Cash and cash equivalents	0	0	0
Accounts receivable:
Utility	93.9	39.6	74.7
Associated companies	0	0.5	0.7
Other	6.3	8.5	6.6
Allowance for doubtful accounts	(4.2)	(3.9)	(2.6)
Inventories:
Natural gas	30.1	33.9	25.1
Materials and supplies	8.2	7.8	7.6
Unamortized purchased gas adjustments	1.6	6.4	39.4
Other regulatory assets	17.2	19.8	18.6
Prepayments	4.6	6	5.7
Other	2.6	2.4	2
Total Current Assets	160.3	121	177.8
Deferred Charges and Other Assets:
Regulatory assets	200.2	201.5	197.4
Deferred income taxes	98.3	101.8	119
Other	58.4	57.8	57.4
Total Deferred Charges and Other Assets	356.9	361.1	373.8
Total Assets	1,670.3	1,616.2	1,618.4
Capitalization:
Paid-in capital and common stock	390.9	390.9	420.9
Retained earnings	419.6	417.8	389.4
Total Shareholders' Equity	810.5	808.7	810.3
Long-term debt (less current portion)	322.6	322.6	277.8
Total Capitalization	1,133.1	1,131.3	1,088.1
Current Liabilities:
Notes payable – associated companies	164.2	142.5	163.1
Accounts payable	78.4	48.4	55
Accounts payable – associated companies	2.5	2.1	3.8
Advance customer billings	9.9	13.1	16.8
Wages and compensation accrued	5.8	6.7	5.4
Customer deposits	19.5	18.6	18.7
Interest accrued	4.8	3.9	3.5
Taxes accrued	26.6	28.3	22
Other regulatory liabilities	10.2	7.6	11.3
Other	3	3.2	2.4
Total Current Liabilities	324.9	274.4	302
Deferred Credits and Other Liabilities:
Pension and postretirement benefit costs	36.2	35	51.5
Asset retirement obligations	137.1	135.7	129.7
Regulatory liabilities	30.6	31.3	39
Other	8.4	8.5	8.1
Total Deferred Credits and Other Liabilities	212.3	210.5	228.3
Commitments and Contingencies (Note 11)
Total Capitalization and Liabilities	$ 1,670.3	$ 1,616.2	$ 1,618.4

CONDENSED CONSOLIDATED BALANC_2

CONDENSED CONSOLIDATED BALANCE SHEETS (UNAUDITED) (Parenthetical) - USD ($) $ in Millions	Dec. 31, 2018	Sep. 30, 2018	Dec. 31, 2017
ASSETS
Non-utility property, accumulated depreciation and amortization	$ 11.1	$ 10.4	$ 8.6
Capitalization:
Common stock, par value (in dollars per share)	$ 1	$ 1	$ 1
Common stock, authorized (in shares)	70,000,000	70,000,000	70,000,000
Common stock, issued (in shares)	50,700,000	50,700,000	48,300,000
Common stock, outstanding (in shares)	50,700,000	50,700,000	48,300,000
Spire Missouri
Capitalization:
Common stock, par value (in dollars per share)	$ 1	$ 1	$ 1
Common stock, authorized (in shares)	50,000,000	50,000,000	50,000,000
Common stock, issued (in shares)	24,577	24,577	24,577
Common stock, outstanding (in shares)	24,577	24,577	24,577
Spire Alabama
Capitalization:
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01	$ 0.01
Common stock, authorized (in shares)	3,000,000	3,000,000	3,000,000
Common stock, issued (in shares)	2,000,000	2,000,000	2,000,000
Common stock, outstanding (in shares)	2,000,000	2,000,000	2,000,000

CONDENSED CONSOLIDATED STATEM_3

CONDENSED CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY (UNAUDITED) - USD ($) $ in Millions	Total	Spire Missouri	Spire Alabama	Common Stock Outstanding	Common Stock OutstandingSpire Missouri	Common Stock OutstandingSpire Alabama	Paid-in Capital	Paid-in CapitalSpire Missouri	Paid-in CapitalSpire Alabama	Retained Earnings	Retained EarningsSpire Missouri	Retained EarningsSpire Alabama	AOCI	[1]	AOCISpire Missouri	[1]
BALANCE at Sep. 30, 2017	$ 1,991.3	$ 1,171	$ 867.4	$ 48.3	$ 0.1	$ 0	$ 1,325.6	$ 756.1	$ 420.9	$ 614.2	$ 416.5	$ 446.5	$ 3.2		$ (1.7)
BALANCE (in shares) at Sep. 30, 2017				48,263,243	24,577	1,972,052
Stockholders' Equity Rollforward
Net income (loss)	116	89.4	(49.6)							116	89.4	(49.6)
Dividend reinvestment plan	0.3						0.3
Dividend reinvestment plan (in shares)				4,618
Stock-based compensation costs	1.9	1.1					1.9	1.1
Stock issued under stock-based compensation plans				$ 0.1			(0.1)
Stock issued under stock-based compensation plans (in shares)				105,434
Employees’ tax withholding for stock-based compensation	(2.9)			$ (0.1)			(2.8)
Employee's tax withholding for stock-based compensation (in shares)				(33,581)
Dividends declared	(27.2)	(13.5)	(7.5)							(27.2)	(13.5)	(7.5)
Other comprehensive loss, net of tax	(0.2)												(0.2)
BALANCE at Dec. 31, 2017	2,079.2	1,248	810.3	$ 48.3	$ 0.1		1,324.9	757.2	420.9	703	492.4	389.4	3		(1.7)
BALANCE (in shares) at Dec. 31, 2017				48,339,714	24,577	1,972,052
BALANCE at Sep. 30, 2018	2,255.4	1,259.9	808.7	$ 50.7	$ 0.1		1,482.7	760.3	390.9	715.6	501.1	417.8	6.4		(1.6)
BALANCE (in shares) at Sep. 30, 2018				50,671,903	24,577	1,972,052
Stockholders' Equity Rollforward
Net income (loss)	67.3	51.2	10.3							67.3	51.2	10.3
Dividend reinvestment plan	0.4						0.4
Dividend reinvestment plan (in shares)				5,063
Stock-based compensation costs	2	1.2					2	1.2
Stock issued under stock-based compensation plans				$ 0.1			(0.1)
Stock issued under stock-based compensation plans (in shares)				74,835
Employees’ tax withholding for stock-based compensation	(2.3)			$ (0.1)			(2.2)
Employee's tax withholding for stock-based compensation (in shares)				(27,633)
Dividends declared	(30)	(9.8)	(8.5)							(30)	(9.8)	(8.5)
Other comprehensive loss, net of tax	(8.2)												(8.2)
BALANCE at Dec. 31, 2018	$ 2,284.6	$ 1,302.5	$ 810.5	$ 50.7	$ 0.1		$ 1,482.8	$ 761.5	$ 390.9	$ 752.9	$ 542.5	$ 419.6	$ (1.8)		$ (1.6)
BALANCE (in shares) at Dec. 31, 2018				50,724,168	24,577	1,972,052
[1]	Accumulated other comprehensive income (loss)

CONSOLIDATED STATEMENTS OF SHAR

CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY (Parenthetical) - $ / shares	3 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Statement Of Stockholders Equity [Abstract]
Dividends declared (in dollars per share)	$ 0.5625	$ 0.5925

CONDENSED CONSOLIDATED STATEM_4

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Operating Activities:
Net Income	$ 67.3	$ 116
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	44.2	40.4
Deferred income taxes and investment tax credits	12.7	(33.6)
Changes in assets and liabilities:
Accounts receivable	(260.5)	(176.7)
Inventories	(2.5)	20.9
Unamortized purchased gas adjustments	20.5	34.6
Accounts payable	158	(2.1)
Delayed/advance customer billings, net	(6.9)	(8.7)
Taxes accrued	(19.1)	(25)
Other assets and liabilities	57.1	50.3
Other	(0.4)	1.8
Net cash provided by (used in) operating activities	70.4	17.9
Investing Activities:
Capital expenditures	(206.8)	(110.8)
Business acquisitions	(7.9)	(16)
Other	(1.5)	0.1
Net cash used in investing activities	(216.2)	(126.7)
Financing Activities:
Issuance of long-term debt	100	30
Repayment of long-term debt	(9.1)	0
Issuance of short-term debt, net	72.5	106.3
Issuance of common stock	0.4	0.3
Dividends paid	(28.8)	(25.8)
Other	(2.2)	(2.7)
Net cash provided by financing activities	132.8	108.1
Net Decrease in Cash, Cash Equivalents, and Restricted Cash	(13)	(0.7)
Cash, Cash Equivalents, and Restricted Cash at Beginning of Period	21.4	7.4
Cash and Cash Equivalents at End of Period	8.4	6.7
Supplemental disclosure of cash paid for:
Interest, net of amounts capitalized	(13.9)	(13.3)
Income taxes	0	0
Cash and Cash Equivalents at Beginning of Period	4.4
Cash and Cash Equivalents at End of Period	8.4	6.7
Spire Missouri
Operating Activities:
Net Income	51.2	89.4
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	27.2	24.8
Deferred income taxes and investment tax credits	7.4	(25)
Changes in assets and liabilities:
Accounts receivable	(124.6)	(143)
Inventories	(2.5)	9.9
Unamortized purchased gas adjustments	16.9	28.8
Accounts payable	50.9	1.6
Delayed/advance customer billings, net	(4.4)	(6.9)
Taxes accrued	(17.4)	(21.7)
Other assets and liabilities	44.5	40.7
Other	1.2	1.1
Net cash provided by (used in) operating activities	50.4	(0.3)
Investing Activities:
Capital expenditures	(92)	(70.5)
Other	0.6	(0.2)
Net cash used in investing activities	(91.4)	(70.7)
Financing Activities:
Issuance of long-term debt	100	0
(Repayments to) borrowings from Spire – net	(37.3)	72.6
Dividends paid	(18.8)	0
Net cash provided by financing activities	43.9	72.6
Supplemental disclosure of cash paid for:
Interest, net of amounts capitalized	(8.3)	(7.6)
Income taxes	0	0
Net Increase (Decrease) in Cash and Cash Equivalents	2.9	1.6
Cash and Cash Equivalents at Beginning of Period	2	2.5
Cash and Cash Equivalents at End of Period	4.9	4.1
Spire Alabama
Operating Activities:
Net Income	10.3	(49.6)
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	13.6	12.8
Deferred income taxes and investment tax credits	3.5	65
Changes in assets and liabilities:
Accounts receivable	(52)	(44.3)
Inventories	3.2	7.7
Unamortized purchased gas adjustments	4.8	5.8
Accounts payable	29.7	14.9
Delayed/advance customer billings, net	(3.2)	(1.8)
Taxes accrued	(1.7)	(1.4)
Other assets and liabilities	9.5	0
Other	(0.4)	0
Net cash provided by (used in) operating activities	17.3	9.1
Investing Activities:
Capital expenditures	(30.1)	(24.9)
Other	(0.4)	0
Net cash used in investing activities	(30.5)	(24.9)
Financing Activities:
Issuance of long-term debt	0	30
(Repayments to) borrowings from Spire – net	21.7	(6.8)
Dividends paid	(8.5)	(7.5)
Net cash provided by financing activities	13.2	15.7
Supplemental disclosure of cash paid for:
Interest, net of amounts capitalized	(3.6)	(3.4)
Income taxes	0	0
Net Increase (Decrease) in Cash and Cash Equivalents	0	(0.1)
Cash and Cash Equivalents at Beginning of Period	0	0.1
Cash and Cash Equivalents at End of Period	$ 0	$ 0

Summary of Significant Accounti

Summary of Significant Accounting Policies	3 Months Ended
	Dec. 31, 2018
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	BASIS OF PRESENTATION – These notes are an integral part of the accompanying unaudited financial statements of Spire Inc. presented on a consolidated basis (“Spire” or the “Company”), Spire Missouri Inc. (“Spire Missouri” or the “Missouri Utilities”) and Spire Alabama Inc. (“Spire Alabama”). Spire Missouri and Spire Alabama are wholly owned subsidiaries of the Company. Spire Missouri, Spire Alabama and the subsidiaries of Spire EnergySouth Inc. (“Spire EnergySouth”) are collectively referred to as the “Utilities.” The subsidiaries of Spire EnergySouth are Spire Gulf Inc. and Spire Mississippi Inc. The accompanying unaudited financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”) for interim financial information with the instructions to Form 10-Q and Rule 10-01 of Regulation S‑X. Accordingly, they do not include all the disclosures required for complete financial statements. In the opinion of management, the accompanying unaudited financial statements include all adjustments (consisting of only normal recurring adjustments) necessary for the fair presentation of the results of operations for the periods presented. This Form 10-Q should be read in conjunction with the Notes to Financial Statements contained in Spire’s, Spire Missouri’s and Spire Alabama’s combined Annual Report on Form 10-K for the fiscal year ended September 30, 2018. The consolidated financial position, results of operations, and cash flows of Spire include the accounts of the Company and all its subsidiaries. Transactions and balances between consolidated entities have been eliminated from the consolidated financial statements of Spire. In compliance with GAAP, transactions between Spire Missouri and Spire Alabama and their affiliates, as well as intercompany balances on their balance sheets, have not been eliminated from their separate financial statements. NATURE OF OPERATIONS – Spire has two reportable segments: Gas Utility and Gas Marketing. The Gas Utility segment consists of the regulated natural gas distribution operations of the Company and is the core business segment of Spire in terms of revenue and earnings. The Gas Utility segment is comprised of the operations of: the Missouri Utilities, serving St. Louis and eastern Missouri (“Spire Missouri East”) and Kansas City and western Missouri (“Spire Missouri West”); Spire Alabama, serving central and northern Alabama; and the subsidiaries of Spire EnergySouth, serving southern Alabama and south-central Mississippi. The Gas Marketing segment includes Spire’s primary gas-related business, Spire Marketing Inc. (“Spire Marketing”), which provides non-regulated natural gas services. The activities of other subsidiaries are reported as Other and are described in Note 10 , Information by Operating Segment. Spire Missouri and Spire Alabama each have a single reportable segment. Nearly all of the Company’s earnings are derived from its Gas Utility segment. Due to the seasonal nature of the Utilities’ business, earnings are typically concentrated during the heating season of November through April each fiscal year. As a result, the interim statements of income for Spire, Spire Missouri and Spire Alabama are not necessarily indicative of annual results or representative of succeeding quarters of the fiscal year. DERIVATIVES – In the course of their business, certain subsidiaries of the Company enter into commitments associated with the purchase or sale of natural gas. Certain of their derivative natural gas contracts are designated as normal purchases or normal sales and, as such, are excluded from the scope of Financial Accounting Standards Board (“FASB”) Accounting Standards Codification (“ASC”) Topic 815, Derivatives and Hedging . Those contracts are accounted for as executory contracts and recorded on an accrual basis. Revenues and expenses from such contracts are recorded using a gross presentation. Contracts not designated as normal purchases or normal sales are recorded as derivatives with changes in fair value recognized in earnings in the periods prior to physical delivery. Certain of Spire Marketing’s wholesale purchase and sale transactions are classified as trading activities for financial reporting purposes. Under GAAP, revenues and expenses associated with trading activities are presented on a net basis in Gas Marketing operating revenues (or expenses, if negative) in the Condensed Consolidated Statements of Income. This net presentation has no effect on operating income or net income. REGULATED OPERATIONS – The Utilities account for their regulated operations in accordance with FASB ASC Topic 980, Regulated Operations . This topic sets forth the application of GAAP for those companies whose rates are established by or are subject to approval by an independent third-party regulator. The provisions of this accounting guidance require, among other things, that financial statements of a regulated enterprise reflect the actions of regulators, where appropriate. These actions may result in the recognition of revenues and expenses in time periods that are different than non-regulated enterprises. When this occurs, costs are deferred as assets in the balance sheet (regulatory assets) and recorded as expenses when those amounts are reflected in rates. In addition, regulators can impose liabilities upon a regulated company for amounts previously collected from customers and for recovery of costs that are expected to be incurred in the future (regulatory liabilities). Management believes that the current regulatory environment supports the continued use of these regulatory accounting principles and that all regulatory assets and regulatory liabilities are recoverable or refundable through the regulatory process. As authorized by the Missouri Public Service Commission (“MoPSC”), the Mississippi Public Service Commission (“MSPSC”) and the Alabama Public Service Commission (“APSC”), the Purchased Gas Adjustment (“PGA”) clauses and Gas Supply Adjustment (“GSA”) riders allow the Utilities to pass through to customers the cost of purchased gas supplies. Regulatory assets and liabilities related to the PGA clauses and the GSA riders are both labeled Unamortized Purchased Gas Adjustments herein. See additional information about regulatory assets and liabilities in Note 4 TRANSACTIONS WITH AFFILIATES – Transactions between affiliates of the Company have been eliminated from the consolidated statements of Spire. Spire Missouri and Spire Alabama borrowed funds from the Company and incurred related interest, as reflected in their separate financial statements, and they participated in normal intercompany shared services transactions Three Months Ended December 31, 2018 2017 Purchases of natural gas from Spire Marketing $ 39.8 $ 22.3 Sales of natural gas to Spire Marketing 1.4 0.1 Transportation services received from Spire NGL Inc. 0.3 0.3 ACCRUED CAPITAL EXPENDITURES – Accrued capital expenditures, shown in the following table, are excluded from capital expenditures in the statements of cash flows until paid. December 31, September 30, December 31, 2018 2018 2017 Spire $ 46.2 $ 62.1 $ 31.8 Spire Missouri 18.1 36.7 15.2 Spire Alabama 9.7 8.9 7.0 NEW ACCOUNTING PRONOUNCEMENTS – Spire, Spire Missouri and Spire Alabama adopted the guidance in Accounting Standards Update (“ASU”) No. 2014-09, Revenue from Contracts with Customers , and related amendments (collectively, “ASC 606”), in the first quarter of fiscal year 2019 using the modified retrospective method applied to all contracts at October 1, 2018. The core principle of ASC 606 is that revenue should be recognized to depict the transfer of control of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. Under the new standard, an entity must identify the performance obligations in a contract, determine the transaction price and allocate the price to specific performance obligations to recognize revenue when the obligation is completed. In addition, ASC 606 requires disclosure of the nature, amount, timing and uncertainty of revenue and cash flows arising from contracts with customers. The adoption of ASC 606 did not result in significant changes to how the Spire, Spire Missouri and Spire Alabama recognize revenue, and therefore, no cumulative effect adjustment to the opening balance of retained earnings was required, and there was no significant impact to financial results after adoption. The adoption did result in changes to the disclosures about revenue, which are included in Note 2 , Revenue. Some revenue arrangements, such as alternative revenue programs and certain derivative contracts, are excluded from the scope of ASC 606 and, therefore, are presented separately in disclosures. Also effective October 1, 2018, Spire, Spire Missouri and Spire Alabama adopted ASU No. Compensation – Retirement Benefits : Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost The amended guidance that the of net periodic pension and postretirement benefit costs presented within line item in the income statement as other compensation costs (except for the amount being capitalized), while other components presented outside the subtotal of operating income and . The amended guidance is applied retrospectively for income statement presentation and prospectively for capitalization. The Company, Spire practical expedient permitting the use of the amounts disclosed in its pension and other postretirement benefit plan note for the prior comparative periods as the estimation basis for applying the retrospective presentation requirements. Accordingly, for the three months ended December 31, 2017, the Company, Spire Missouri and Spire Alabama reclassified net benefit (income) costs of $(1.1), $0.2 and $(1.0), respectively, from “operation and maintenance” to “other income, net” or “other (expense) income, net.” The corresponding annual amounts to be reclassified for the years ended September 30, 2018, 2017 and 2016 are $14.4, $19.2 and $9.6 for the Company, respectively, $17.2, $17.2 and $11.2 for Spire Missouri, respectively, and $(2.0), $2.2 and $(1.6) for Spire Alabama, respectively. For Spire Missouri, Spire Alabama, and the Company’s other rate-regulated entities, all components of net benefit cost have historically been recovered from customers as a component of utility plant and will continue to be recovered in the same manner over the depreciable lives of the related plant assets; therefore, for those entities, the components that are no longer eligible to be capitalized as a component of plant under GAAP will be reported as regulatory assets In February 2016, the FASB issued ASU No. 2016-02, Leases In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments – Credit Losses: Measurement of Credit Losses on Financial Instruments In August 2017, the FASB issued ASU No. 2017-12, Derivatives and Hedging: Targeted Improvements to Accounting for Hedging Activities In August 2018, the FASB issued ASU No. Intangibles – Goodwill and Other – Internal-Use Software: Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract

Revenue

Revenue	3 Months Ended
	Dec. 31, 2018
Revenue From Contract With Customer [Abstract]
Revenue	The following tables show revenue disaggregated by source and customer type. Three Months Ended December 31, 2018 Spire Gas Utility: Residential $ 393.6 Commercial & industrial 130.3 Transportation 29.5 Off-system & other incentive 14.9 Other customer revenue 12.7 Total revenue from contracts with customers 581.0 Changes in accrued revenue under alternative revenue programs (5.8 ) Total Gas Utility operating revenues 575.2 Gas Marketing: Revenue from contracts with retail customers 25.8 Revenue from wholesale derivative contracts — Total Gas Marketing operating revenues 25.8 Other 5.4 Total before eliminations 606.4 Intersegment eliminations (see Note 10) (4.4 ) Total Operating Revenues $ 602.0 Spire Missouri Residential $ 302.1 Commercial & industrial 89.1 Transportation 9.0 Off-system & other incentive 14.9 Other customer revenue 2.6 Total revenue from contracts with customers 417.7 Changes in accrued revenue under alternative revenue programs (4.5 ) Total Operating Revenues $ 413.2 Three Months Ended December 31, 2018 Spire Alabama Residential $ 75.4 Commercial & industrial 31.4 Transportation 18.2 Other customer revenue 9.6 Total revenue from contracts with customers 134.6 Changes in accrued revenue under alternative revenue programs (1.1 ) Total Operating Revenues $ 133.5 The Utilities sell natural gas to residential and other customers. The sale of natural gas is governed by the various state utility commissions, which set rates, charges, and terms and conditions of service, collectively included in a “tariff.” The performance obligation, which related to the promise to provide natural gas, is satisfied over time as the customer simultaneously receives and consumes the natural gas, and revenue is recognized accordingly. The Utilities’ transportation revenue relates to the promise to transport the specified quantities of natural gas at tariff rates. This performance obligation is satisfied over time as the gas is transported, and revenue is recognized as invoiced monthly. The Utilities have alternative revenue programs (“ARPs”), which represent an agreement between the utility and its regulator, currently consisting of decoupling mechanisms (also known as weather normalization adjustments) and incentive programs (primarily Alabama’s Cost Control Measure). When the criteria to recognize additional (or reduced) revenue from ARPs have been met, the Utilities establish a regulatory asset (or liability). When amounts previously recognized for ARPs are billed, the Utilities reduce the regulatory asset (or liability) and increase (or decrease) accounts receivable. Billed amounts, which are part of the overall tariff paid by customers, are included in revenue from contracts with customers, while the change in the related regulatory asset or liability is presented as revenue from ARPs. Depending on whether the beginning accrued ARP balance was a regulatory asset or liability and depending on the size and direction of the current period accrual, the amount presented as revenue from ARPs could be negative. The Utilities read meters and bill customers on monthly cycles. The Missouri Utilities, Spire Gulf and Spire Mississippi record their gas utility revenues from gas sales and transportation services on an accrual basis that includes estimated amounts for gas delivered but not yet billed. The accruals for unbilled revenues are reversed in the subsequent accounting period when meters are actually read and customers are billed. Spire Alabama records natural gas distribution revenues in accordance with the tariff established by the APSC. Unbilled revenue is accrued in an amount equal to the related gas cost, as profit margin is not considered earned until billed. Spire’s other subsidiaries, including Spire Marketing, record revenues when earned, as the product is delivered or as services are performed. Gas Marketing’s contracts are derivatives. The wholesale contracts (with producers, municipalities, and utility companies) are subject to derivative accounting. The retail contracts (with large commercial and industrial customers) are designated as “normal purchase, normal sale” arrangements and are therefore accounted for as revenue from contracts with customers. The performance obligation is satisfied over time by the transfer of control of natural gas to the customer, and revenue is recognized as invoiced monthly. Payments are generally required within 30 days of billing, and contracts generally do not have a significant financing component. Spire’s revenues are not subject to significant returns, refunds, or warranty obligations. Spire, Spire Missouri, and Spire Alabama have elected to apply a “right to invoice” practical expedient, recognizing revenue for volumes delivered for which they have a right to invoice, as long as that amount corresponds with the value to the customer. Disclosures about remaining performance obligations are not required because either contracts have an original expected duration of one year or less, or revenue is recognized under the right to invoice practical expedient, or both. Sales taxes imposed on applicable Spire Alabama and Spire Missouri sales are billed to customers. These amounts are not recorded in the statements of income but are recorded as tax collections payable and included in the “Other” line of the Current Liabilities section of the balance sheets. Gross receipts taxes associated with the Company’s natural gas utility services are imposed on the Company, Spire Missouri, and Spire Alabama and billed to its customers. The revenue and expense amounts are recorded gross in the “Operating Revenues” and “Taxes, other than income taxes” lines, respectively, in the statements of income. The following table presents gross receipts taxes recorded as revenues: Three Months Ended December 31, 2018 2017 Spire $ 25.9 $ 23.1 Spire Missouri 18.5 16.2 Spire Alabama 6.3 5.6

Earnings Per Share

Earnings Per Share	3 Months Ended
	Dec. 31, 2018
Earnings Per Share [Abstract]
Earnings Per Share	Three Months Ended December 31, 2018 2017 Basic Earnings Per Share: Net Income $ 67.3 $ 116.0 Less: Income allocated to participating securities 0.1 0.2 Income Available to Common Shareholders $ 67.2 $ 115.8 Weighted Average Shares Outstanding (in millions) 50.6 48.2 Basic Earnings Per Share $ 1.33 $ 2.40 Diluted Earnings Per Share: Net Income $ 67.3 $ 116.0 Less: Income allocated to participating securities 0.1 0.2 Income Available to Common Shareholders $ 67.2 $ 115.8 Weighted Average Shares Outstanding (in millions) 50.6 48.2 Dilutive Effect of Restricted Stock and Restricted Stock Units (in millions)* 0.2 0.2 Weighted Average Diluted Shares (in millions) 50.8 48.4 Diluted Earnings Per Share $ 1.32 $ 2.39 * Calculation excludes certain outstanding shares (shown in millions by period at the right) attributable to stock units subject to performance or market conditions and restricted stock, which could have a dilutive effect in the future 0.4 0.3

Regulatory Matters

Regulatory Matters	3 Months Ended
	Dec. 31, 2018
Regulated Operations [Abstract]
Regulatory Matters	As explained in Note 1 Regulated Operations December 31, September 30, December 31, Spire 2018 2018 2017 Regulatory Assets: Current: Pension and postretirement benefit costs $ 30.2 $ 30.2 $ 43.0 Unamortized purchased gas adjustments 3.0 8.2 77.9 Other 30.2 34.4 28.4 Total Current Regulatory Assets 63.4 72.8 149.3 Noncurrent: Future income taxes due from customers 99.1 96.3 113.1 Pension and postretirement benefit costs 350.0 364.9 394.8 Cost of removal 134.0 133.4 123.9 Energy efficiency 33.6 32.8 30.0 Other 38.4 42.4 54.8 Total Noncurrent Regulatory Assets 655.1 669.8 716.6 Total Regulatory Assets $ 718.5 $ 742.6 $ 865.9 Regulatory Liabilities: Current: Rate Stabilization and Equalization ("RSE") adjustment $ 2.5 $ — $ 1.0 Refundable negative salvage 4.6 5.2 7.9 Unamortized purchased gas adjustments 6.1 2.9 1.0 Other 23.8 27.6 11.6 Total Current Regulatory Liabilities 37.0 35.7 21.5 Noncurrent: Deferred taxes due to customers 169.8 178.3 177.4 Pension and postretirement benefit costs 27.1 27.8 31.5 Refundable negative salvage — — 3.8 Accrued cost of removal 59.4 63.6 81.7 Unamortized purchased gas adjustments 16.7 4.7 6.5 Other 90.4 80.2 34.2 Total Noncurrent Regulatory Liabilities 363.4 354.6 335.1 Total Regulatory Liabilities $ 400.4 $ 390.3 $ 356.6 December 31, September 30, December 31, Spire Missouri 2018 2018 2017 Regulatory Assets: Current: Pension and postretirement benefit costs $ 21.9 $ 21.9 $ 34.9 Unamortized purchased gas adjustments — 1.0 38.5 Other 7.8 7.8 3.3 Total Current Regulatory Assets 29.7 30.7 76.7 Noncurrent: Future income taxes due from customers 96.7 94.4 113.1 Pension and postretirement benefit costs 279.8 292.5 315.8 Energy efficiency 33.6 32.8 30.0 Other 17.5 21.4 25.2 Total Noncurrent Regulatory Assets 427.6 441.1 484.1 Total Regulatory Assets $ 457.3 $ 471.8 $ 560.8 Regulatory Liabilities: Current: Unamortized purchased gas adjustments $ 5.8 $ 1.9 $ — Other 14.8 14.8 2.7 Total Current Regulatory Liabilities 20.6 16.7 2.7 Noncurrent: Deferred taxes due to customers 152.4 161.1 159.2 Accrued cost of removal 35.2 39.8 52.0 Unamortized purchased gas adjustments 16.7 4.7 6.5 Other 75.4 69.3 23.5 Total Noncurrent Regulatory Liabilities 279.7 274.9 241.2 Total Regulatory Liabilities $ 300.3 $ 291.6 $ 243.9 December 31, September 30, December 31, Spire Alabama 2018 2018 2017 Regulatory Assets: Current: Pension and postretirement benefit costs $ 7.3 $ 7.3 $ 7.2 Unamortized purchased gas adjustments 1.6 6.4 39.4 Other 9.9 12.5 11.4 Total Current Regulatory Assets 18.8 26.2 58.0 Noncurrent: Pension and postretirement benefit costs 63.0 64.8 70.8 Cost of removal 134.0 133.4 123.9 Other 3.2 3.3 2.7 Total Noncurrent Regulatory Assets 200.2 201.5 197.4 Total Regulatory Assets $ 219.0 $ 227.7 $ 255.4 Regulatory Liabilities: Current: RSE adjustment $ 2.5 $ — $ 1.0 Refundable negative salvage 4.6 5.2 7.9 Other 3.1 2.4 2.4 Total Current Regulatory Liabilities 10.2 7.6 11.3 Noncurrent: Pension and postretirement benefit costs 27.1 27.8 31.5 Refundable negative salvage — — 3.9 Other 3.5 3.5 3.6 Total Noncurrent Regulatory Liabilities 30.6 31.3 39.0 Total Regulatory Liabilities $ 40.8 $ 38.9 $ 50.3 A portion of the Company’s and Spire Missouri’s regulatory assets are not earning a return, as shown in the table below: December 31, September 30, December 31, 2018 2018 2017 Spire Pension and postretirement benefit costs $ 141.2 $ 148.4 $ 193.8 Future income taxes due from customers 99.1 96.3 113.1 Other 14.3 15.1 11.2 Total Regulatory Assets Not Earning a Return $ 254.6 $ 259.8 $ 318.1 Spire Missouri Pension and postretirement benefit costs $ 141.2 $ 148.4 $ 193.8 Future income taxes due from customers 96.7 94.4 113.1 Other 14.3 15.1 11.2 Total Regulatory Assets Not Earning a Return $ 252.2 $ 257.9 $ 318.1 Like all the Company’s regulatory assets, these regulatory assets are expected to be recovered from customers in future rates. The recovery period for the future income taxes due from customers and pension and other postretirement benefit costs could be 20 years or longer, based on current Internal Revenue Service (“IRS”) guidelines and average remaining service life of active participants, respectively. The other items not earning a return are expected to be recovered over a period not to exceed 15 years, consistent with precedent set by the MoPSC. Spire Alabama does not have any regulatory assets that are not earning a return. On March 7, 2018, the MoPSC issued its order in two general rate cases, approving new tariffs that became effective on April 19, 2018. On April 25, 2018, Spire Missouri filed an appeal of the MoPSC’s order related to the disallowance of certain pension costs incurred prior to 1997 ($28.8), real estate sold in 2014 ($1.8), and rate case expenses ($0.9) to Missouri’s Southern District Court of Appeals. The appeals process is ongoing. The rate case order also allowed for a Weather Normalization Adjustment Rider for residential customers which provides volumetric revenue protection and improved weather mitigation compared to previous rate designs. There are currently two open cases on this rider requesting a calculation clarification. In September 2016 and February 2017, Spire Missouri filed Infrastructure System Replacement Surcharge (“ISRS”) cases for both Spire Missouri East and Spire Missouri West (the “2016/2017 ISRS Cases”). The Missouri Office of the Public Counsel (“OPC”) appealed the MoPSC’s decisions approving these cases to Missouri’s Western District Court of Appeals, arguing that they contained ISRS-ineligible costs. In November 2017, the appellate court reversed the MoPSC’s decision in the 2016/2017 ISRS Cases and remanded the case back to the MoPSC. In June 2018, Spire Missouri filed to establish new ISRS rates in both its East and West divisions (the “2018 ISRS Cases”). In September 2018, the MoPSC issued orders finding that Spire Missouri’s ISRS petitions in the 2016/2017 ISRS Cases and the 2018 ISRS Cases included ISRS-ineligible costs related to the replacement of plastic pipe components and approved rates in the 2018 ISRS Cases providing annual revenues of $2.6 for Spire Missouri East and $5.4 for Spire Missouri West. Spire is appealing the removal of costs related to plastic in all cases in the Western District Court. On January 14, 2019, Spire Missouri refiled requests with additional information for approximately $3.2 of the ISRS revenues that were removed by the MoPSC in previous cases and filed new ISRS applications for both its East and West service territories. The new applications include requests for the approval of ISRS revenues of $7.4 for Spire Missouri East and $8.4 for Spire Missouri West related to investments made or forecasted from July 1, 2018, through January 31, 2019. Spire Missouri is seeking an Accounting Authority Order to record a regulatory asset (or liability) representing the increases (or decreases) in the annual MoPSC assessment from the amount currently reflected in rates, beginning July 1, 2018, and continuing until its next rate case. For the first twelve months, the impact is a $1.7 (51%) increase. The latest action on the matter was a reply brief filed by Spire Missouri on January 11, 2019. As part of the annual update for RSE, on November 30, 2018, Spire Alabama filed an increase for rate year 2019 of $8.7, which became effective December 1, 2018. At December 31, 2018, an estimated RSE reduction for the January 31, 2019 quarterly point of test of $4.1 was recorded to bring the expected rate of return on average common equity at the end of the year to within the allowed rate of return. On January 25, 2019, the Federal Energy Regulatory Commission (“FERC”) approved the Company’s application to combine its two adjacent natural gas storage facilities in Wyoming into one FERC certificate with a market-based tariff.

Financing Arrangements and Long

Financing Arrangements and Long-term Debt	3 Months Ended
	Dec. 31, 2018
Debt Disclosure [Abstract]
Financing Arrangements and Long-term Debt	Spire, Spire Missouri and Spire Alabama have a syndicated revolving credit facility pursuant to a loan agreement with 11 banks, expiring October 31, 2023. The loan agreement has an aggregate credit commitment of $975.0, including sublimits of $300.0 for Spire, $475.0 for Spire Missouri, and $200.0 for Spire Alabama. These sublimits may be reallocated from time to time among the three borrowers within the $975.0 aggregate commitment, with commitments fees applied for each borrower relative to its credit rating. Spire may use its line to provide for the funding needs of various subsidiaries. The agreement also contains financial covenants limiting each borrower’s consolidated total debt, including short-term debt, to no more than 70% of its total capitalization. As defined in the line of credit, on December 31, 2018, total debt was 55% of total capitalization for the consolidated Company, 50% for Spire Missouri, and 38% for Spire Alabama. There were no borrowings against this credit facility as of December 31, 2018, September 30, 2018, or December 31, 2017. Spire has a commercial paper program (“Program”) pursuant to which Spire may issue short-term, unsecured commercial paper notes (“Notes”). Amounts available under the Program may be borrowed, repaid and re-borrowed from time to time, with the aggregate face or principal amount of the Notes outstanding under the Program at any time not to exceed $975.0. The Notes may have maturities of up to 365 days from date of issue. Information about Spire’s consolidated short-term borrowings and about Spire Missouri’s and Spire Alabama’s borrowings from Spire is presented in the following table. As of December 31, 2018, $509.9 of Spire’s short-term borrowings were used to support lending to the Utilities. Spire Commercial Paper Borrowings Spire Missouri Borrowings from Spire Spire Alabama Borrowings from Spire Three Months Ended December 31, 2018 Weighted average borrowings outstanding $622.9 $343.9 $152.3 Weighted average interest rate 2.7% 2.7% 2.7% Range of borrowings outstanding $562.3 - $689.3 $273.6 - $404.9 $140.8 - $169.2 As of December 31, 2018 Borrowings outstanding $626.1 $308.0 $164.2 Weighted average interest rate 3.1% 3.1% 3.1% As of September 30, 2018 Borrowings outstanding $553.6 $345.3 $142.5 Weighted average interest rate 2.4% 2.3% 2.3% As of December 31, 2017 Borrowings outstanding $583.6 $275.6 $163.1 Weighted average interest rate 2.0% 2.0% 2.0% The long-term debt agreements of Spire, Spire Missouri and Spire Alabama contain customary covenants and default provisions. As of December 31, 2018, there were no events of default under these covenants. Interest expense shown on Spire’s consolidated statements of income and Spire Missouri’s statements of comprehensive income is net of the capitalized interest amounts shown in the following table. Three Months Ended December 31, 2018 2017 Spire $ 1.2 $ 0.4 Spire Missouri 0.5 0.2 In October 2018, the Company settled a $10.0 non-interest-bearing note. In December 2018, Spire Missouri entered into a new loan agreement (“Loan Agreement”) providing for a term loan of $100.0, which was fully funded on December 3, 2018, and which matures on December 1, 2021, subject to optional prepayment by Spire. Borrowings under the Loan Agreement bear interest at a rate determined by reference to the London Interbank Offered Rate (“LIBOR”), plus a margin based on the Borrower’s senior debt rating as determined by Standard & Poor’s Rating Services or Moody’s Investors Services, Inc. On January 15, 2019, Spire Alabama entered into the Second Supplement to Master Note Purchase Agreement with certain institutional investors. Pursuant to the terms of that supplement, Spire Alabama closed a $90.0 private placement of 4.64% Series 2019A Senior Notes due January 15, 2049, to those institutional investors. The notes bear interest from the date of issuance, payable semi-annually on the 15th day of July and January of each year, commencing on July 15, 2019. The notes are senior unsecured obligations of Spire Alabama, rank equal in right to payment with all its other senior unsecured indebtedness, and have make-whole and par call options. Spire Alabama used the proceeds to repay short-term debt and for general corporate purposes.

Fair Value of Financial Instrum

Fair Value of Financial Instruments	3 Months Ended
	Dec. 31, 2018
Fair Value Disclosures [Abstract]
Fair Value of Financial Instruments	The carrying amounts and estimated fair values of financial instruments not measured at fair value on a recurring basis are shown in the following tables, classified according to the fair value hierarchy. There were no such instruments classified as Level 3 (significant unobservable inputs) as of December 31, 2018, September 30, 2018, or December 31, 2017. The carrying amounts of cash and cash equivalents and short-term debt approximate fair value due to the short maturity of these instruments. The fair values of long-term debt are estimated based on market prices for similar issues. Refer to Note 7 Classification of Estimated Fair Value Carrying Amount Fair Value Quoted Prices in Active Markets (Level 1) Significant Observable Inputs (Level 2) Spire As of December 31, 2018 Cash and cash equivalents $ 8.4 $ 8.4 $ 8.4 $ — Short-term debt 626.1 626.1 — 626.1 Long-term debt, including current portion 2,167.0 2,133.9 — 2,133.9 As of September 30, 2018 Cash and cash equivalents $ 4.4 $ 4.4 $ 4.4 $ — Short-term debt 553.6 553.6 — 553.6 Long-term debt, including current portion 2,075.6 2,074.0 — 2,074.0 As of December 31, 2017 Cash and cash equivalents $ 6.7 $ 6.7 $ 6.7 $ — Short-term debt 583.6 583.6 — 583.6 Long-term debt, including current portion 2,135.5 2,280.1 — 2,280.1 Spire Missouri As of December 31, 2018 Cash and cash equivalents $ 4.9 $ 4.9 $ 4.9 $ — Short-term debt 308.0 308.0 — 308.0 Long-term debt, including current portion 974.5 997.3 — 997.3 As of September 30, 2018 Cash and cash equivalents $ 2.0 $ 2.0 $ 2.0 $ — Short-term debt 345.3 345.3 — 345.3 Long-term debt, including current portion 874.4 906.6 — 906.6 As of December 31, 2017 Cash and cash equivalents $ 4.1 $ 4.1 $ 4.1 $ — Short-term debt 275.6 275.6 — 275.6 Long-term debt, including current portion 974.1 1,068.6 — 1,068.6 Spire Alabama As of December 31, 2018 Short-term debt $ 164.2 $ 164.2 $ — $ 164.2 Long-term debt 322.6 311.3 — 311.3 As of September 30, 2018 Short-term debt $ 142.5 $ 142.5 $ — $ 142.5 Long-term debt 322.6 321.7 — 321.7 As of December 31, 2017 Short-term debt $ 163.1 $ 163.1 $ — $ 163.1 Long-term debt 277.8 303.5 — 303.5

Fair Value Measurements

Fair Value Measurements	3 Months Ended
	Dec. 31, 2018
Fair Value Disclosures [Abstract]
Fair Value Measurements	The information presented below categorizes the assets and liabilities in the balance sheets that are accounted for at fair value on a recurring basis in periods subsequent to initial recognition. The mutual funds included in Level 1 are valued based on exchange-quoted market prices of individual securities. The mutual funds included in Level 2 are valued based on the closing net asset value per unit. Derivative instruments included in Level 1 are valued using quoted market prices on the New York Mercantile Exchange (“NYMEX”) or the Intercontinental Exchange (“ICE”). Derivative instruments classified in Level 2 include physical commodity derivatives that are valued using broker or dealer quotation services whose prices are derived principally from, or are corroborated by, observable market inputs. Also included in Level 2 are certain derivative instruments that have values that are similar to, and correlate with, quoted prices for exchange-traded instruments in active markets. Derivative instruments included in Level 3 are valued using generally unobservable inputs that are based upon the best information available and reflect management’s assumptions about how market participants would price the asset or liability. The Level 3 balances as of December 31, 2018, September 30, 2018, and December 31, 2017, consisted of gas commodity contracts. The Company’s and the Utilities’ policy is to recognize transfers between the levels of the fair value hierarchy, if any, as of the beginning of the interim reporting period in which circumstances change or events occur to cause the transfer. The mutual funds are included in “Other Investments” on the Company’s balance sheets and in “Other Property and Investments” on Spire Missouri’s balance sheets. Derivative assets and liabilities, including receivables and payables associated with cash margin requirements, are presented net in the balance sheets when a legally enforceable netting agreement exists between the Company, Spire Missouri, or Spire Alabama and the counterparty to a derivative contract. Spire Quoted Prices in Active Markets (Level 1) Significant Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Effects of Netting and Cash Margin Receivables /Payables Total As of December 31, 2018 ASSETS Gas Utility: US stock/bond mutual funds $ 18.3 $ — $ — $ — $ 18.3 NYMEX/ICE natural gas contracts 1.2 — — (1.2 ) — Gas Marketing: NYMEX/ICE natural gas contracts 0.2 11.9 — (9.3 ) 2.8 Natural gas commodity contracts — 30.8 — (8.3 ) 22.5 Other: U.S. stock/bond mutual funds 12.5 — — — 12.5 Total $ 32.2 $ 42.7 $ — $ (18.8 ) $ 56.1 LIABILITIES Gas Utility: NYMEX/ICE natural gas contracts $ 0.9 $ — $ — $ (0.9 ) $ — Gas Marketing: NYMEX/ICE natural gas contracts 0.6 8.8 — (9.4 ) — Natural gas commodity contracts — 25.1 0.3 (8.3 ) 17.1 Other: Interest rate swaps — 7.5 — — 7.5 Total $ 1.5 $ 41.4 $ 0.3 $ (18.6 ) $ 24.6 Quoted Prices in Active Markets (Level 1) Significant Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Effects of Netting and Cash Margin Receivables /Payables Total As of September 30, 2018 ASSETS Gas Utility: US stock/bond mutual funds $ 20.3 $ — $ — $ — $ 20.3 NYMEX/ICE natural gas contracts 2.7 — — (2.7 ) — Gas Marketing: NYMEX/ICE natural gas contracts 0.2 4.0 — (4.2 ) — Natural gas commodity contracts — 17.5 — (1.5 ) 16.0 Other: U.S. stock/bond mutual funds 8.9 — — — 8.9 Interest rate swaps — 3.0 — — 3.0 Total $ 32.1 $ 24.5 $ — $ (8.4 ) $ 48.2 LIABILITIES Gas Utility: NYMEX/ICE natural gas contracts $ 1.9 $ — $ — $ (1.9 ) $ — Gas Marketing: NYMEX/ICE natural gas contracts 0.9 10.5 — (11.4 ) — Natural gas commodity contracts — 7.5 0.2 (1.5 ) 6.2 Total $ 2.8 $ 18.0 $ 0.2 $ (14.8 ) $ 6.2 As of December 31, 2017 ASSETS Gas Utility: US stock/bond mutual funds $ 19.5 $ 4.0 $ — $ — $ 23.5 NYMEX/ICE natural gas contracts 0.5 — — (0.5 ) — Gas Marketing: NYMEX/ICE natural gas contracts 2.4 4.0 — (6.1 ) 0.3 Natural gas commodity contracts — 7.7 — (4.3 ) 3.4 Total $ 22.4 $ 15.7 $ — $ (10.9 ) $ 27.2 LIABILITIES Gas Utility: NYMEX/ICE natural gas contracts $ 2.7 $ — $ — $ (2.7 ) $ — Gas Marketing: NYMEX/ICE natural gas contracts 1.1 5.9 — (7.0 ) — Natural gas commodity contracts — 8.9 0.4 (4.3 ) 5.0 Other: Interest rate swaps — 0.8 — — 0.8 Total $ 3.8 $ 15.6 $ 0.4 $ (14.0 ) $ 5.8 Spire Missouri Quoted Prices in Active Markets (Level 1) Significant Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Effects of Netting and Cash Margin Receivables /Payables Total As of December 31, 2018 ASSETS US stock/bond mutual funds $ 18.3 $ — $ — $ — $ 18.3 NYMEX/ICE natural gas contracts 1.2 — — (1.2 ) — Total $ 19.5 $ — $ — $ (1.2 ) $ 18.3 LIABILITIES NYMEX/ICE natural gas contracts $ 0.9 $ — $ — $ (0.9 ) $ — As of September 30, 2018 ASSETS US stock/bond mutual funds $ 20.3 $ — $ — $ — $ 20.3 NYMEX/ICE natural gas contracts 2.7 — — (2.7 ) — Total $ 23.0 $ — $ — $ (2.7 ) $ 20.3 LIABILITIES NYMEX/ICE natural gas contracts $ 1.9 $ — $ — $ (1.9 ) $ — As of December 31, 2017 ASSETS US stock/bond mutual funds $ 19.5 $ 4.0 $ — $ — $ 23.5 NYMEX/ICE natural gas contracts 0.5 — — (0.5 ) — Total $ 20.0 $ 4.0 $ — $ (0.5 ) $ 23.5 LIABILITIES NYMEX/ICE natural gas contracts $ 2.7 $ — $ — $ (2.7 ) $ — Spire Alabama Spire Alabama occasionally utilizes a gasoline derivative program to stabilize the cost of fuel used in operations. As of December 31, 2018, September 30, 2018, and December 31, 2017, Spire Alabama had no outstanding derivative contracts.

Concentration of Credit Risk

Concentration of Credit Risk	3 Months Ended
	Dec. 31, 2018
Risks And Uncertainties [Abstract]
Concentration of Credit Risk	Other than in Spire Marketing, Spire has no significant concentrations of credit risk. A significant portion of Spire Marketing’s transactions are with (or are associated with) energy producers, utility companies, and pipelines. The concentration of transactions with these counterparties has the potential to affect the Company’s overall exposure to credit risk, either positively or negatively, in that each of these three groups may be affected similarly by changes in economic, industry, or other conditions. To manage this risk, as well as credit risk from significant counterparties in these and other industries, Spire Marketing has established procedures to determine the creditworthiness of its counterparties. These procedures include obtaining credit ratings and credit reports, analyzing counterparty financial statements to assess financial condition, and considering the industry environment in which the counterparty operates. This information is monitored on an ongoing basis. In some instances, Spire Marketing may require credit assurances such as prepayments, letters of credit, or parental guarantees. In addition, Spire Marketing may enter into netting arrangements to mitigate credit risk with counterparties in the energy industry with whom it conducts both sales and purchases of natural gas. Sales are typically made on an unsecured credit basis with payment due the month following delivery. Accounts receivable amounts are closely monitored and provisions for uncollectible amounts are accrued when losses are probable. Spire Marketing records accounts receivable, accounts payable, and prepayments for physical sales and purchases of natural gas on a gross basis. The amount included in its accounts receivable attributable to energy producers and their marketing affiliates totaled $26.0 at December 31, 2018 ($13.2 reflecting netting arrangements). Spire Marketing’s accounts receivable attributable to utility companies and their marketing affiliates totaled $121.9 at December 31, 2018 ($102.5 reflecting netting arrangements). Spire Marketing also has concentrations of credit risk with pipeline companies associated with its natural gas receivable and with certain individually significant counterparties. At December 31, 2018, the amounts included in accounts receivable from its five largest counterparties (in terms of net accounts receivable exposure) totaled $41.8 ($35.0 reflecting netting arrangements). Four of these five counterparties are investment-grade rated companies. The fifth is not rated but is a subsidiary of an investment-grade rated company.

Pension Plans and Other Postret

Pension Plans and Other Postretirement Benefits	3 Months Ended
	Dec. 31, 2018
Defined Contribution Pension And Other Postretirement Plans Disclosure [Abstract]
Pension Plans and Other Postretirement Benefits	Pension Plans Spire and the Utilities maintain pension plans for their employees. The Missouri Utilities have non-contributory, defined benefit, trusteed forms of pension plans covering the majority of their employees. Plan assets consist primarily of corporate and United States (“U.S.”) government obligations and a growth segment consisting of exposure to equity markets, commodities, real estate and inflation-indexed securities, achieved through derivative instruments. Spire Alabama has non-contributory, defined benefit, trusteed forms of pension plans covering the majority of its employees. Qualified plan assets are comprised of mutual and commingled funds consisting of U.S. equities with varying strategies, global equities, alternative investments, and fixed income investments. The net periodic pension cost included the following components: Three Months Ended December 31, 2018 2017 Spire Service cost – benefits earned during the period $ 4.8 $ 5.2 Interest cost on projected benefit obligation* 7.1 6.9 Expected return on plan assets* (9.1 ) (9.7 ) Amortization of prior service credit* (0.3 ) (0.3 ) Amortization of actuarial loss* 2.3 3.1 Subtotal 4.8 5.2 Regulatory adjustment 9.9 4.3 Net pension cost $ 14.7 $ 9.5 Spire Missouri Service cost – benefits earned during the period $ 3.1 $ 3.3 Interest cost on projected benefit obligation* 5.0 4.9 Expected return on plan assets* (6.4 ) (7.2 ) Amortization of prior service cost* 0.2 0.2 Amortization of actuarial loss* 2.1 2.6 Subtotal 4.0 3.8 Regulatory adjustment 8.0 2.4 Net pension cost $ 12.0 $ 6.2 Spire Alabama Service cost – benefits earned during the period $ 1.5 $ 1.6 Interest cost on projected benefit obligation* 1.5 1.4 Expected return on plan assets* (1.8 ) (1.7 ) Amortization of prior service credit* (0.4 ) (0.5 ) Amortization of actuarial loss* 0.2 0.5 Subtotal 1.0 1.3 Regulatory adjustment 1.7 1.7 Net pension cost $ 2.7 $ 3.0 * Denotes pension expense line items that are recorded below the operating income line in the income statements, in the line items “Other Income, Net” or “Other (Expense) Income, Net.” Pursuant to the provisions of the Missouri Utilities’ and Spire Alabama’s pension plans, pension obligations may be satisfied by monthly annuities, lump-sum cash payments, or special termination benefits. Lump-sum payments are recognized as settlements (which can result in gains or losses) only if the total of such payments exceeds the sum of service and interest costs in a specific year. Special termination benefits, when offered, are also recognized as settlements which can result in gains or losses. For the first quarter of both fiscal 2019 and fiscal 2018, no pension plans met the criteria for settlement recognition. The funding policy of the Utilities is to contribute an amount not less than the minimum required by government funding standards, nor more than the maximum deductible amount for federal income tax purposes. Fiscal 2019 contributions to Spire Missouri’s pension plans through December 31, 2018, were $1.4 to the qualified trusts and none to non-qualified plans. There were no fiscal 2019 contributions to the Spire Alabama pension plans through December 31, 2018. Contributions to the qualified trusts of the Missouri Utilities’ pension plans for the remainder of fiscal 2019 are anticipated to be $25.3. No contributions to Spire Alabama’s pension plans are expected to be required for the remainder of fiscal 2019. Other Postretirement Benefits Spire and the Utilities provide certain life insurance benefits at retirement. Spire Missouri plans provide for medical insurance after early retirement until age 65. For retirements prior to January 1, 2015, the Spire Missouri West plans provided medical insurance after retirement until death. The Spire Alabama plans provide medical insurance upon retirement until death for certain retirees depending on the type of employee and the date the employee was originally hired. Net periodic postretirement benefit costs consisted of the following components: Three Months Ended December 31, 2018 2017 Spire Service cost – benefits earned during the period $ 1.9 $ 2.3 Interest cost on accumulated postretirement benefit obligation* 2.3 2.2 Expected return on plan assets* (4.1 ) (3.5 ) Amortization of actuarial (gain) loss* (0.1 ) 0.2 Subtotal — 1.2 Regulatory adjustment 2.4 0.1 Net postretirement benefit cost $ 2.4 $ 1.3 Spire Missouri Service cost – benefits earned during the period $ 1.7 $ 2.2 Interest cost on accumulated postretirement benefit obligation* 1.7 1.8 Expected return on plan assets* (2.8 ) (2.4 ) Amortization of prior service cost* 0.1 0.1 Amortization of actuarial (gain) loss* (0.1 ) 0.2 Subtotal 0.6 1.9 Regulatory adjustment 2.9 0.5 Net postretirement benefit cost $ 3.5 $ 2.4 Spire Alabama Service cost – benefits earned during the period $ 0.1 $ — Interest cost on accumulated postretirement benefit obligation* 0.5 0.4 Expected return on plan assets* (1.2 ) (1.0 ) Amortization of prior service credit* (0.1 ) (0.1 ) Subtotal (0.7 ) (0.7 ) Regulatory adjustment (0.5 ) (0.4 ) Net postretirement benefit income $ (1.2 ) $ (1.1 ) * Denotes other postretirement expense line items that are recorded below the operating income line in the income statements, in the line items “Other Income, Net” or “Other (Expense) Income, Net.” Missouri and Alabama state laws provide for the recovery in rates of costs accrued pursuant to GAAP provided that such costs are funded through an independent, external funding mechanism. The Utilities have established Voluntary Employees’ Beneficiary Association (“VEBA”) and Rabbi Trusts as external funding mechanisms. The assets of the VEBA and Rabbi Trusts consist primarily of money market securities and mutual funds invested in stocks and bonds. The Utilities’ funding policy is to contribute amounts to the trusts equal to the periodic benefit cost calculated pursuant to GAAP as recovered in rates. There have been no

Information by Operating Segmen

Information by Operating Segment	3 Months Ended
	Dec. 31, 2018
Segment Reporting [Abstract]
INFORMATION BY OPERATING SEGMENT	The Company has two reportable segments: Gas Utility and Gas Marketing. The Gas Utility segment is the aggregation of the operations of the Utilities. The Gas Marketing segment includes the results of Spire Marketing, a subsidiary engaged in the non-regulated marketing of natural gas and related activities, including utilizing natural gas storage contracts for providing natural gas sales. Other components of the Company’s consolidated information include: • unallocated corporate items, including certain debt and associated interest costs; • Spire STL Pipeline LLC, a subsidiary of Spire constructing and planning the operation of a 65-mile FERC-regulated pipeline to deliver natural gas into eastern Missouri; • Spire Storage, providing physical natural gas storage services; and • Spire’s subsidiaries engaged in the operation of a propane pipeline, compression of natural gas, and risk management, among other activities. Accounting policies are described in Note 1 Management evaluates the performance of the operating segments based on the computation of net economic earnings. Net economic earnings exclude from reported net income the after-tax impacts of fair value accounting and timing adjustments associated with energy-related transactions, the impacts of acquisition, divestiture and restructuring activities, and the largely non-cash impacts of other non-recurring or unusual items such as certain regulatory, legislative, or GAAP standard-setting actions. Gas Utility Gas Marketing Other Eliminations Consolidated Three Months Ended December 31, 2018 Operating Revenues: Revenues from external customers $ 573.8 $ 25.8 $ 2.4 $ — $ 602.0 Intersegment revenues 1.4 — 3.0 (4.4 ) — Total Operating Revenues 575.2 25.8 5.4 (4.4 ) 602.0 Operating Expenses: Gas Utility Natural and propane gas 291.8 — — (40.1 ) 251.7 Operation and maintenance 104.9 — — (2.4 ) 102.5 Depreciation and amortization 43.7 — — — 43.7 Taxes, other than income taxes 39.2 — — — 39.2 Total Gas Utility Operating Expenses 479.6 — — (42.5 ) 437.1 Gas Marketing and Other — 13.3 8.4 38.1 59.8 Total Operating Expenses 479.6 13.3 8.4 (4.4 ) 496.9 Operating Income (Loss) $ 95.6 $ 12.5 $ (3.0 ) $ — $ 105.1 Net Economic Earnings (Loss) $ 66.4 $ 8.3 $ (8.8 ) $ — $ 65.9 Gas Utility Gas Marketing Other Eliminations Consolidated Three Months Ended December 31, 2017 Operating Revenues: Revenues from external customers $ 541.9 $ 19.6 $ 0.3 $ — $ 561.8 Intersegment revenues 0.1 — 2.5 (2.6 ) — Total Operating Revenues 542.0 19.6 2.8 (2.6 ) 561.8 Operating Expenses: Gas Utility Natural and propane gas 263.4 — — (22.6 ) 240.8 Operation and maintenance 100.9 — — (1.9 ) 99.0 Depreciation and amortization 40.3 — — — 40.3 Taxes, other than income taxes 36.7 — — — 36.7 Total Gas Utility Operating Expenses 441.3 — — (24.5 ) 416.8 Gas Marketing and Other — 14.6 4.5 21.9 41.0 Total Operating Expenses 441.3 14.6 4.5 (2.6 ) 457.8 Operating Income (Loss) $ 100.7 $ 5.0 $ (1.7 ) $ — $ 104.0 Net Economic Earnings (Loss) $ 59.5 $ 3.6 $ (5.2 ) $ — $ 57.9 December 31, September 30, December 31, 2018 2018 2017 Total Assets: Gas Utility $ 5,843.7 $ 5,606.7 $ 5,611.7 Gas Marketing 416.7 295.3 233.5 Other 2,535.6 2,508.0 2,427.7 Eliminations (1,563.8 ) (1,566.4 ) (1,571.8 ) Total Assets $ 7,232.2 $ 6,843.6 $ 6,701.1 The following table reconciles the Company’s net economic earnings to net income. Three Months Ended December 31, 2018 2017 Net Income $ 67.3 $ 116.0 Adjustments, pre-tax: Unrealized (gain) loss on energy-related derivatives (2.2 ) 0.8 Realized gain on economic hedges prior to the sale of the physical commodity — (0.1 ) Acquisition, divestiture and restructuring activities 0.4 1.7 Income tax effect of adjustments 0.4 (0.6 ) Effect of the Tax Cuts and Jobs Act — (59.9 ) Net Economic Earnings $ 65.9 $ 57.9

Commitments and Contingencies

Commitments and Contingencies	3 Months Ended
	Dec. 31, 2018
Commitments And Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments The Company and the Utilities have entered into contracts with various counterparties, expiring on dates through 2032, for the storage, transportation, and supply of natural gas. Minimum payments required under the contracts in place at December 31, 2018, are estimated at $1,691.8, $731.8, and $248.3 for the Company, Spire Missouri, and Spire Alabama, respectively. Additional contracts are generally entered into prior to or during the heating season of November through April. The Utilities recover their costs from customers in accordance with their PGA clauses or GSA riders. Contingencies The Company and the Utilities account for contingencies, including environmental liabilities, in accordance with accounting standards under the loss contingency guidance of ASC Topic 450, Contingencies In addition to matters noted below, the Company and the Utilities are involved in other litigation, claims, and investigations arising in the normal course of business. Management, after discussion with counsel, believes the final outcome will not have a material effect on the statements of income, balance sheets, and statements of cash flows of the Company, Spire Missouri, or Spire Alabama. However, there is uncertainty in the valuation of pending claims and prediction of litigation results. The Company and the Utilities own and operate natural gas distribution, transmission, and storage facilities, the operations of which are subject to various environmental laws, regulations, and interpretations. While environmental issues resulting from such operations arise in the ordinary course of business, such issues have not materially affected the Company’s or Utilities’ financial position and results of operations. As environmental laws, regulations, and their interpretations change, the Company or the Utilities may incur additional environmental liabilities that may result in additional costs, which may be material. In the natural gas industry, many gas distribution companies have incurred environmental liabilities associated with sites they or their predecessor companies formerly owned or operated where manufactured gas operations took place. The Utilities each have former manufactured gas plant (“MGP”) operations in their respective service territories. To the extent costs are incurred associated with environmental remediation activities, the Utilities would request authority from their respective regulators to defer such costs (less any amounts received from insurance proceeds or as contributions from other potentially responsible parties (“PRPs”)) and collect them through future rates. Spire Missouri Spire Missouri has identified three former MGP sites in the city of St. Louis, Missouri (the “City”) where costs have been incurred and claims have been asserted. Spire Missouri has enrolled two of the sites in the Missouri Department of Natural Resources (“MDNR”) Brownfields/Voluntary Cleanup Program (“BVCP”). The third site is the result of a relatively new claim assertion by the United States Environmental Protection Agency (“EPA”) and such claim is currently being investigated. In conjunction with redevelopment of one of the sites, Spire Missouri and another former owner of the site entered into an agreement (the “Remediation Agreement”) with the City development agencies, the developer, and an environmental consultant that obligates one of the City agencies and the environmental consultant to remediate the site and obtain a No Further Action letter from the MDNR. The Remediation Agreement also provides for a release of Spire Missouri and the other former site owner from certain liabilities related to the past and current environmental condition of the site and requires the developer and the environmental consultant to maintain certain insurance coverage, including remediation cost containment, premises pollution liability, and professional liability. The operative provisions of the Remediation Agreement were triggered on December 20, 2010, on which date Spire Missouri and the other former site owner, as full consideration under the Remediation Agreement, paid a small percentage of the cost of remediation of the site. The amount paid by Spire Missouri did not materially impact the financial condition, results of operations, or cash flows of the Company. Spire Missouri has not owned the second site for many years. In a letter dated June 29, 2011, the Attorney General for the State of Missouri informed Spire Missouri that the MDNR had completed an investigation of the site. The Attorney General requested that Spire Missouri participate in the follow up investigations of the site. In a letter dated January 10, 2012, Spire Missouri stated that it would participate in future environmental response activities at the site in conjunction with other PRPs that are willing to contribute to such efforts in a meaningful and equitable fashion. Accordingly, Spire Missouri entered into a cost sharing agreement for remedial investigation with other PRPs. To date, MDNR has not approved the agreement, so remedial investigation has not yet occurred. Additionally, in correspondence dated November 30, 2016, Region 7 of the EPA has asserted that Spire Missouri is liable under Section 107(a) of the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (“CERCLA”) for alleged coal gas waste contamination at a third site in the northern portion of the City on which Spire Missouri operated a MGP. Spire Missouri has not owned or operated the site for over 70 years. Spire Missouri and the site owner have met with the EPA and reviewed its assertions. Both Spire Missouri and the site owner have notified the EPA that information and data provided by the EPA to date does not rise to the level of documenting a threat to the public health or environment. As such, Spire Missouri requested more information from the EPA, some of which would also be utilized to identify other former owners and operators of the site that could be added as PRPs. To date, Spire Missouri has not received a response from the EPA. Spire Missouri has notified its insurers that it seeks reimbursement for costs incurred in the past and future potential liabilities associated with the MGP sites. While some of the insurers have denied coverage and reserved their rights, Spire Missouri retains the right to seek potential reimbursements from them. On March 10, 2015, Spire Missouri received a Section 104(e) information request under CERCLA from EPA Region 7 regarding the former Thompson Chemical/Superior Solvents site in the City. In turn, Spire Missouri issued a Freedom of Information Act (“FOIA”) request to the EPA on April 3, 2015, in an effort to identify the basis of the inquiry. The FOIA response from the EPA was received on July 15, 2015 and a response was provided to the EPA on August 15, 2015. Spire Missouri has received no further inquiry from the EPA regarding this matter. In its western service area, Spire Missouri has seven owned MGP sites enrolled in the BVCP, including Joplin MGP #1, St. Joseph MGP #1, Kansas City Coal Gas Station B, Kansas City Station A Railroad area, Kansas City Coal Gas Station A North, Kansas City Coal Gas Station A South, and Independence MGP #2. Source removal has been conducted at all of the owned sites since 2003 with the exception of Joplin. On September 15, 2016, a request was made with the MDNR for a restrictive covenant use limitation with respect to Joplin. Remediation efforts at the seven sites are at various stages of completion, ranging from groundwater monitoring and sampling following source removal activities to the aforementioned request in respect to Joplin. As part of its participation in the BVCP, Spire Missouri communicates regularly with the MDNR with respect to its remediation efforts and monitoring activities at these sites. On May 11, 2015, MDNR approved the next phase of investigation at the Kansas City Station A North and Railroad areas. To date, costs incurred for all Missouri Utilities’ MGP sites for investigation, remediation and monitoring these sites have not been material. However, the amount of costs relative to future remedial actions at these and other sites is unknown and may be material. The actual future costs that Spire Missouri may incur could be materially higher or lower depending upon several factors, including whether remediation actions will be required, final selection and regulatory approval of any remedial actions, changing technologies and government regulations, the ultimate ability of other PRPs to pay, and any insurance recoveries. In 2013, Spire Missouri retained an outside consultant to conduct probabilistic cost modeling of 19 former MGP sites owned or operated by Spire Missouri. The purpose of this analysis was to develop an estimated range of probabilistic future liability for each site. That analysis, completed in August 2014, provided a range of demonstrated possible future expenditures to investigate, monitor and remediate all 19 MGP sites. Spire Missouri has recorded its best estimate of the probable expenditures that relate to these matters. The amount is not material. Spire Missouri and the Company do not expect potential liabilities that may arise from remediating these sites to have a material impact on their future financial condition or results of operations. Spire Alabama On December 17, 2013, an incident occurred at a Housing Authority apartment complex in Birmingham, Alabama that resulted in one fatality, personal injuries and property damage. Spire Alabama cooperated with the National Transportation Safety Board (“NTSB”) which investigated the incident. The NTSB report of findings was issued on March 30, 2016 and no safety recommendations, fines, or penalties were contained therein. Spire Alabama has been named as a defendant in several lawsuits arising from the incident, some of which remain pending. Spire Alabama does not expect potential liabilities that may arise from these lawsuits to have a material impact on its future financial condition or results of operations. Spire Alabama is in the chain of title of nine former MGP sites, four of which it still owns, and five former manufactured gas distribution sites, one of which it still owns. Spire Alabama does not foresee a probable or reasonably estimable loss associated with these sites. Spire Alabama and the Company do not expect potential liabilities that may arise from remediating these sites to have a material impact on their future financial condition or results of operations. In 2012, Spire Alabama responded to an EPA Request for Information Pursuant to Section 104 of CERCLA relating to the 35th Avenue Superfund Site located in North Birmingham, Jefferson County, Alabama. Spire Alabama was identified as a PRP under CERCLA for the cleanup of the site or costs the EPA incurs in cleaning up the site. At this point, Spire Alabama has not been provided information that would allow it to determine the extent, if any, of its potential liability with respect to the 35th Avenue Superfund Site and vigorously denies its inclusion as a PRP. Spire In addition to those discussed above for Spire Missouri and Spire Alabama, Spire is aware of the following contingent matters. Since April 2012, a total of 14 lawsuits encompassing more than 1,600 plaintiffs have been filed against Spire Gulf in Mobile County Circuit Court alleging that in the first half of 2008, Spire Gulf spilled tert-butyl mercaptan, an odorant added to natural gas for safety reasons, in Eight Mile, Alabama. All of the lawsuits have been substantially settled, with the exception of 13 individuals who rejected their settlement offers and whose claims remain pending. Those remaining claims allege nuisance, fraud and negligence causes of actions and seek unspecified compensatory and punitive damages. A claim has been made against the insurance carriers requesting reimbursement for costs accrued in respect to this spill, and a related receivable has been recorded. The Company does not expect potential liabilities that may arise from these lawsuits to have a material impact on its future financial condition or results of operations. In February 2018, the Company was made aware of a complaint filed with the U.S. Department of Housing and Urban Development (“HUD”) by the South Alabama Center for Fair Housing and the National Community Reinvestment Coalition. The complaint alleges that the Company discriminated against unspecified residents of Eight Mile, Alabama, on the basis of race in violation of the Fair Housing Act by failing to adequately address the odorant release that occurred in 2008. The Company believes there is no basis for the complaint, HUD has no jurisdiction in the matter, and there will be no material impact on its future financial condition or results of operations.

Income Taxes

Income Taxes	3 Months Ended
	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Income Taxes	The Tax Cuts and Jobs Act (“TCJA”) was signed into law on December 22, 2017, with an effective date of January 1, 2018, for substantially all of the provisions. The specific provisions related to regulated public utilities in the TCJA generally allow for the continued deductibility of interest expense, the elimination of full expensing for tax purposes of certain property acquired after September 27, 2017, and the continuation of certain rate normalization requirements for accelerated depreciation benefits. The Department of the Treasury (“Treasury”) has issued proposed regulations associated with the deductibility of interest expense, but further clarification of certain provisions is expected. Treasury has also issued proposed regulations on bonus depreciation which allow full expensing for certain property acquired in tax years beginning prior to January 1, 2018. As indicated in Note 1 Regulated Operations

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	3 Months Ended
	Dec. 31, 2018
Accounting Policies [Abstract]
Basis of Presentation	BASIS OF PRESENTATION – These notes are an integral part of the accompanying unaudited financial statements of Spire Inc. presented on a consolidated basis (“Spire” or the “Company”), Spire Missouri Inc. (“Spire Missouri” or the “Missouri Utilities”) and Spire Alabama Inc. (“Spire Alabama”). Spire Missouri and Spire Alabama are wholly owned subsidiaries of the Company. Spire Missouri, Spire Alabama and the subsidiaries of Spire EnergySouth Inc. (“Spire EnergySouth”) are collectively referred to as the “Utilities.” The subsidiaries of Spire EnergySouth are Spire Gulf Inc. and Spire Mississippi Inc. The accompanying unaudited financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”) for interim financial information with the instructions to Form 10-Q and Rule 10-01 of Regulation S‑X. Accordingly, they do not include all the disclosures required for complete financial statements. In the opinion of management, the accompanying unaudited financial statements include all adjustments (consisting of only normal recurring adjustments) necessary for the fair presentation of the results of operations for the periods presented. This Form 10-Q should be read in conjunction with the Notes to Financial Statements contained in Spire’s, Spire Missouri’s and Spire Alabama’s combined Annual Report on Form 10-K for the fiscal year ended September 30, 2018. The consolidated financial position, results of operations, and cash flows of Spire include the accounts of the Company and all its subsidiaries. Transactions and balances between consolidated entities have been eliminated from the consolidated financial statements of Spire. In compliance with GAAP, transactions between Spire Missouri and Spire Alabama and their affiliates, as well as intercompany balances on their balance sheets, have not been eliminated from their separate financial statements.
Derivatives	DERIVATIVES – In the course of their business, certain subsidiaries of the Company enter into commitments associated with the purchase or sale of natural gas. Certain of their derivative natural gas contracts are designated as normal purchases or normal sales and, as such, are excluded from the scope of Financial Accounting Standards Board (“FASB”) Accounting Standards Codification (“ASC”) Topic 815, Derivatives and Hedging . Those contracts are accounted for as executory contracts and recorded on an accrual basis. Revenues and expenses from such contracts are recorded using a gross presentation. Contracts not designated as normal purchases or normal sales are recorded as derivatives with changes in fair value recognized in earnings in the periods prior to physical delivery. Certain of Spire Marketing’s wholesale purchase and sale transactions are classified as trading activities for financial reporting purposes. Under GAAP, revenues and expenses associated with trading activities are presented on a net basis in Gas Marketing operating revenues (or expenses, if negative) in the Condensed Consolidated Statements of Income. This net presentation has no effect on operating income or net income.
Regulated Operations	REGULATED OPERATIONS – The Utilities account for their regulated operations in accordance with FASB ASC Topic 980, Regulated Operations . This topic sets forth the application of GAAP for those companies whose rates are established by or are subject to approval by an independent third-party regulator. The provisions of this accounting guidance require, among other things, that financial statements of a regulated enterprise reflect the actions of regulators, where appropriate. These actions may result in the recognition of revenues and expenses in time periods that are different than non-regulated enterprises. When this occurs, costs are deferred as assets in the balance sheet (regulatory assets) and recorded as expenses when those amounts are reflected in rates. In addition, regulators can impose liabilities upon a regulated company for amounts previously collected from customers and for recovery of costs that are expected to be incurred in the future (regulatory liabilities). Management believes that the current regulatory environment supports the continued use of these regulatory accounting principles and that all regulatory assets and regulatory liabilities are recoverable or refundable through the regulatory process. As authorized by the Missouri Public Service Commission (“MoPSC”), the Mississippi Public Service Commission (“MSPSC”) and the Alabama Public Service Commission (“APSC”), the Purchased Gas Adjustment (“PGA”) clauses and Gas Supply Adjustment (“GSA”) riders allow the Utilities to pass through to customers the cost of purchased gas supplies. Regulatory assets and liabilities related to the PGA clauses and the GSA riders are both labeled Unamortized Purchased Gas Adjustments herein. See additional information about regulatory assets and liabilities in Note 4
Transactions with Affiliates	TRANSACTIONS WITH AFFILIATES – Transactions between affiliates of the Company have been eliminated from the consolidated statements of Spire. Spire Missouri and Spire Alabama borrowed funds from the Company and incurred related interest, as reflected in their separate financial statements, and they participated in normal intercompany shared services transactions
Accrued Capital Expenditures	Accrued capital expenditures, shown in the following table, are excluded from capital expenditures in the statements of cash flows until paid.
New Accounting Pronouncements	NEW ACCOUNTING PRONOUNCEMENTS – Spire, Spire Missouri and Spire Alabama adopted the guidance in Accounting Standards Update (“ASU”) No. 2014-09, Revenue from Contracts with Customers , and related amendments (collectively, “ASC 606”), in the first quarter of fiscal year 2019 using the modified retrospective method applied to all contracts at October 1, 2018. The core principle of ASC 606 is that revenue should be recognized to depict the transfer of control of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. Under the new standard, an entity must identify the performance obligations in a contract, determine the transaction price and allocate the price to specific performance obligations to recognize revenue when the obligation is completed. In addition, ASC 606 requires disclosure of the nature, amount, timing and uncertainty of revenue and cash flows arising from contracts with customers. The adoption of ASC 606 did not result in significant changes to how the Spire, Spire Missouri and Spire Alabama recognize revenue, and therefore, no cumulative effect adjustment to the opening balance of retained earnings was required, and there was no significant impact to financial results after adoption. The adoption did result in changes to the disclosures about revenue, which are included in Note 2 , Revenue. Some revenue arrangements, such as alternative revenue programs and certain derivative contracts, are excluded from the scope of ASC 606 and, therefore, are presented separately in disclosures. Also effective October 1, 2018, Spire, Spire Missouri and Spire Alabama adopted ASU No. Compensation – Retirement Benefits : Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost The amended guidance that the of net periodic pension and postretirement benefit costs presented within line item in the income statement as other compensation costs (except for the amount being capitalized), while other components presented outside the subtotal of operating income and . The amended guidance is applied retrospectively for income statement presentation and prospectively for capitalization. The Company, Spire practical expedient permitting the use of the amounts disclosed in its pension and other postretirement benefit plan note for the prior comparative periods as the estimation basis for applying the retrospective presentation requirements. Accordingly, for the three months ended December 31, 2017, the Company, Spire Missouri and Spire Alabama reclassified net benefit (income) costs of $(1.1), $0.2 and $(1.0), respectively, from “operation and maintenance” to “other income, net” or “other (expense) income, net.” The corresponding annual amounts to be reclassified for the years ended September 30, 2018, 2017 and 2016 are $14.4, $19.2 and $9.6 for the Company, respectively, $17.2, $17.2 and $11.2 for Spire Missouri, respectively, and $(2.0), $2.2 and $(1.6) for Spire Alabama, respectively. For Spire Missouri, Spire Alabama, and the Company’s other rate-regulated entities, all components of net benefit cost have historically been recovered from customers as a component of utility plant and will continue to be recovered in the same manner over the depreciable lives of the related plant assets; therefore, for those entities, the components that are no longer eligible to be capitalized as a component of plant under GAAP will be reported as regulatory assets In February 2016, the FASB issued ASU No. 2016-02, Leases In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments – Credit Losses: Measurement of Credit Losses on Financial Instruments In August 2017, the FASB issued ASU No. 2017-12, Derivatives and Hedging: Targeted Improvements to Accounting for Hedging Activities In August 2018, the FASB issued ASU No. Intangibles – Goodwill and Other – Internal-Use Software: Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Tables)	3 Months Ended
	Dec. 31, 2018
Accounting Policies [Abstract]
Schedule of Inter-Company Transactions	In addition, Spire Missouri’s other transactions with affiliates included Three Months Ended December 31, 2018 2017 Purchases of natural gas from Spire Marketing $ 39.8 $ 22.3 Sales of natural gas to Spire Marketing 1.4 0.1 Transportation services received from Spire NGL Inc. 0.3 0.3
Schedule of capital expenditures excluded from statement of cash flow	Accrued capital expenditures, shown in the following table, are excluded from capital expenditures in the statements of cash flows until paid. December 31, September 30, December 31, 2018 2018 2017 Spire $ 46.2 $ 62.1 $ 31.8 Spire Missouri 18.1 36.7 15.2 Spire Alabama 9.7 8.9 7.0

Revenue (Tables)

Revenue (Tables)	3 Months Ended
	Dec. 31, 2018
Revenue From Contract With Customer [Abstract]
Schedule of Revenue Disaggregated by Source and Customer Type	The following tables show revenue disaggregated by source and customer type. Three Months Ended December 31, 2018 Spire Gas Utility: Residential $ 393.6 Commercial & industrial 130.3 Transportation 29.5 Off-system & other incentive 14.9 Other customer revenue 12.7 Total revenue from contracts with customers 581.0 Changes in accrued revenue under alternative revenue programs (5.8 ) Total Gas Utility operating revenues 575.2 Gas Marketing: Revenue from contracts with retail customers 25.8 Revenue from wholesale derivative contracts — Total Gas Marketing operating revenues 25.8 Other 5.4 Total before eliminations 606.4 Intersegment eliminations (see Note 10) (4.4 ) Total Operating Revenues $ 602.0 Spire Missouri Residential $ 302.1 Commercial & industrial 89.1 Transportation 9.0 Off-system & other incentive 14.9 Other customer revenue 2.6 Total revenue from contracts with customers 417.7 Changes in accrued revenue under alternative revenue programs (4.5 ) Total Operating Revenues $ 413.2 Three Months Ended December 31, 2018 Spire Alabama Residential $ 75.4 Commercial & industrial 31.4 Transportation 18.2 Other customer revenue 9.6 Total revenue from contracts with customers 134.6 Changes in accrued revenue under alternative revenue programs (1.1 ) Total Operating Revenues $ 133.5
Schedule of Gross Receipts Taxes	The following table presents gross receipts taxes recorded as revenues: Three Months Ended December 31, 2018 2017 Spire $ 25.9 $ 23.1 Spire Missouri 18.5 16.2 Spire Alabama 6.3 5.6

Earnings Per Share (Tables)

Earnings Per Share (Tables)	3 Months Ended
	Dec. 31, 2018
Earnings Per Share [Abstract]
Schedule of Basic and Diluted Earnings Per Share	Three Months Ended December 31, 2018 2017 Basic Earnings Per Share: Net Income $ 67.3 $ 116.0 Less: Income allocated to participating securities 0.1 0.2 Income Available to Common Shareholders $ 67.2 $ 115.8 Weighted Average Shares Outstanding (in millions) 50.6 48.2 Basic Earnings Per Share $ 1.33 $ 2.40 Diluted Earnings Per Share: Net Income $ 67.3 $ 116.0 Less: Income allocated to participating securities 0.1 0.2 Income Available to Common Shareholders $ 67.2 $ 115.8 Weighted Average Shares Outstanding (in millions) 50.6 48.2 Dilutive Effect of Restricted Stock and Restricted Stock Units (in millions)* 0.2 0.2 Weighted Average Diluted Shares (in millions) 50.8 48.4 Diluted Earnings Per Share $ 1.32 $ 2.39 * Calculation excludes certain outstanding shares (shown in millions by period at the right) attributable to stock units subject to performance or market conditions and restricted stock, which could have a dilutive effect in the future 0.4 0.3

Regulatory Matters (Tables)

Regulatory Matters (Tables)	3 Months Ended
	Dec. 31, 2018
Regulated Operations [Abstract]
Schedule of Regulatory Assets and Liabilities	The following regulatory assets and regulatory liabilities, including purchased gas adjustments, were reflected in the balance sheets of the Company, Spire Missouri and Spire Alabama as of December 31, 2018, September 30, 2018, and December 31, 2017. December 31, September 30, December 31, Spire 2018 2018 2017 Regulatory Assets: Current: Pension and postretirement benefit costs $ 30.2 $ 30.2 $ 43.0 Unamortized purchased gas adjustments 3.0 8.2 77.9 Other 30.2 34.4 28.4 Total Current Regulatory Assets 63.4 72.8 149.3 Noncurrent: Future income taxes due from customers 99.1 96.3 113.1 Pension and postretirement benefit costs 350.0 364.9 394.8 Cost of removal 134.0 133.4 123.9 Energy efficiency 33.6 32.8 30.0 Other 38.4 42.4 54.8 Total Noncurrent Regulatory Assets 655.1 669.8 716.6 Total Regulatory Assets $ 718.5 $ 742.6 $ 865.9 Regulatory Liabilities: Current: Rate Stabilization and Equalization ("RSE") adjustment $ 2.5 $ — $ 1.0 Refundable negative salvage 4.6 5.2 7.9 Unamortized purchased gas adjustments 6.1 2.9 1.0 Other 23.8 27.6 11.6 Total Current Regulatory Liabilities 37.0 35.7 21.5 Noncurrent: Deferred taxes due to customers 169.8 178.3 177.4 Pension and postretirement benefit costs 27.1 27.8 31.5 Refundable negative salvage — — 3.8 Accrued cost of removal 59.4 63.6 81.7 Unamortized purchased gas adjustments 16.7 4.7 6.5 Other 90.4 80.2 34.2 Total Noncurrent Regulatory Liabilities 363.4 354.6 335.1 Total Regulatory Liabilities $ 400.4 $ 390.3 $ 356.6 December 31, September 30, December 31, Spire Missouri 2018 2018 2017 Regulatory Assets: Current: Pension and postretirement benefit costs $ 21.9 $ 21.9 $ 34.9 Unamortized purchased gas adjustments — 1.0 38.5 Other 7.8 7.8 3.3 Total Current Regulatory Assets 29.7 30.7 76.7 Noncurrent: Future income taxes due from customers 96.7 94.4 113.1 Pension and postretirement benefit costs 279.8 292.5 315.8 Energy efficiency 33.6 32.8 30.0 Other 17.5 21.4 25.2 Total Noncurrent Regulatory Assets 427.6 441.1 484.1 Total Regulatory Assets $ 457.3 $ 471.8 $ 560.8 Regulatory Liabilities: Current: Unamortized purchased gas adjustments $ 5.8 $ 1.9 $ — Other 14.8 14.8 2.7 Total Current Regulatory Liabilities 20.6 16.7 2.7 Noncurrent: Deferred taxes due to customers 152.4 161.1 159.2 Accrued cost of removal 35.2 39.8 52.0 Unamortized purchased gas adjustments 16.7 4.7 6.5 Other 75.4 69.3 23.5 Total Noncurrent Regulatory Liabilities 279.7 274.9 241.2 Total Regulatory Liabilities $ 300.3 $ 291.6 $ 243.9 December 31, September 30, December 31, Spire Alabama 2018 2018 2017 Regulatory Assets: Current: Pension and postretirement benefit costs $ 7.3 $ 7.3 $ 7.2 Unamortized purchased gas adjustments 1.6 6.4 39.4 Other 9.9 12.5 11.4 Total Current Regulatory Assets 18.8 26.2 58.0 Noncurrent: Pension and postretirement benefit costs 63.0 64.8 70.8 Cost of removal 134.0 133.4 123.9 Other 3.2 3.3 2.7 Total Noncurrent Regulatory Assets 200.2 201.5 197.4 Total Regulatory Assets $ 219.0 $ 227.7 $ 255.4 Regulatory Liabilities: Current: RSE adjustment $ 2.5 $ — $ 1.0 Refundable negative salvage 4.6 5.2 7.9 Other 3.1 2.4 2.4 Total Current Regulatory Liabilities 10.2 7.6 11.3 Noncurrent: Pension and postretirement benefit costs 27.1 27.8 31.5 Refundable negative salvage — — 3.9 Other 3.5 3.5 3.6 Total Noncurrent Regulatory Liabilities 30.6 31.3 39.0 Total Regulatory Liabilities $ 40.8 $ 38.9 $ 50.3
Schedule of Regulatory Assets Not Earning a Return	A portion of the Company’s and Spire Missouri’s regulatory assets are not earning a return, as shown in the table below: December 31, September 30, December 31, 2018 2018 2017 Spire Pension and postretirement benefit costs $ 141.2 $ 148.4 $ 193.8 Future income taxes due from customers 99.1 96.3 113.1 Other 14.3 15.1 11.2 Total Regulatory Assets Not Earning a Return $ 254.6 $ 259.8 $ 318.1 Spire Missouri Pension and postretirement benefit costs $ 141.2 $ 148.4 $ 193.8 Future income taxes due from customers 96.7 94.4 113.1 Other 14.3 15.1 11.2 Total Regulatory Assets Not Earning a Return $ 252.2 $ 257.9 $ 318.1

Financing Arrangements and Lo_2

Financing Arrangements and Long-term Debt (Tables)	3 Months Ended
	Dec. 31, 2018
Debt Disclosure [Abstract]
Schedule of Spire Missouri and Alabama Short-term Borrowings	Information about Spire’s consolidated short-term borrowings and about Spire Missouri’s and Spire Alabama’s borrowings from Spire is presented in the following table. As of December 31, 2018, $509.9 of Spire’s short-term borrowings were used to support lending to the Utilities. Spire Commercial Paper Borrowings Spire Missouri Borrowings from Spire Spire Alabama Borrowings from Spire Three Months Ended December 31, 2018 Weighted average borrowings outstanding $622.9 $343.9 $152.3 Weighted average interest rate 2.7% 2.7% 2.7% Range of borrowings outstanding $562.3 - $689.3 $273.6 - $404.9 $140.8 - $169.2 As of December 31, 2018 Borrowings outstanding $626.1 $308.0 $164.2 Weighted average interest rate 3.1% 3.1% 3.1% As of September 30, 2018 Borrowings outstanding $553.6 $345.3 $142.5 Weighted average interest rate 2.4% 2.3% 2.3% As of December 31, 2017 Borrowings outstanding $583.6 $275.6 $163.1 Weighted average interest rate 2.0% 2.0% 2.0%
Summary Capitalized Interest	Interest expense shown on Spire’s consolidated statements of income and Spire Missouri’s statements of comprehensive income is net of the capitalized interest amounts shown in the following table. Three Months Ended December 31, 2018 2017 Spire $ 1.2 $ 0.4 Spire Missouri 0.5 0.2

Fair Value of Financial Instr_2

Fair Value of Financial Instruments (Tables)	3 Months Ended
	Dec. 31, 2018
Fair Value Disclosures [Abstract]
Summary of Financial Instruments Measured at Fair Value on Recurring Basis	Classification of Estimated Fair Value Carrying Amount Fair Value Quoted Prices in Active Markets (Level 1) Significant Observable Inputs (Level 2) Spire As of December 31, 2018 Cash and cash equivalents $ 8.4 $ 8.4 $ 8.4 $ — Short-term debt 626.1 626.1 — 626.1 Long-term debt, including current portion 2,167.0 2,133.9 — 2,133.9 As of September 30, 2018 Cash and cash equivalents $ 4.4 $ 4.4 $ 4.4 $ — Short-term debt 553.6 553.6 — 553.6 Long-term debt, including current portion 2,075.6 2,074.0 — 2,074.0 As of December 31, 2017 Cash and cash equivalents $ 6.7 $ 6.7 $ 6.7 $ — Short-term debt 583.6 583.6 — 583.6 Long-term debt, including current portion 2,135.5 2,280.1 — 2,280.1 Spire Missouri As of December 31, 2018 Cash and cash equivalents $ 4.9 $ 4.9 $ 4.9 $ — Short-term debt 308.0 308.0 — 308.0 Long-term debt, including current portion 974.5 997.3 — 997.3 As of September 30, 2018 Cash and cash equivalents $ 2.0 $ 2.0 $ 2.0 $ — Short-term debt 345.3 345.3 — 345.3 Long-term debt, including current portion 874.4 906.6 — 906.6 As of December 31, 2017 Cash and cash equivalents $ 4.1 $ 4.1 $ 4.1 $ — Short-term debt 275.6 275.6 — 275.6 Long-term debt, including current portion 974.1 1,068.6 — 1,068.6 Spire Alabama As of December 31, 2018 Short-term debt $ 164.2 $ 164.2 $ — $ 164.2 Long-term debt 322.6 311.3 — 311.3 As of September 30, 2018 Short-term debt $ 142.5 $ 142.5 $ — $ 142.5 Long-term debt 322.6 321.7 — 321.7 As of December 31, 2017 Short-term debt $ 163.1 $ 163.1 $ — $ 163.1 Long-term debt 277.8 303.5 — 303.5

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	3 Months Ended
	Dec. 31, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Schedule of Fair Value Assets and Liabilities Measured on Recurring Basis	The information presented below categorizes the assets and liabilities in the balance sheets that are accounted for at fair value on a recurring basis in periods subsequent to initial recognition. The mutual funds included in Level 1 are valued based on exchange-quoted market prices of individual securities. The mutual funds included in Level 2 are valued based on the closing net asset value per unit. Derivative instruments included in Level 1 are valued using quoted market prices on the New York Mercantile Exchange (“NYMEX”) or the Intercontinental Exchange (“ICE”). Derivative instruments classified in Level 2 include physical commodity derivatives that are valued using broker or dealer quotation services whose prices are derived principally from, or are corroborated by, observable market inputs. Also included in Level 2 are certain derivative instruments that have values that are similar to, and correlate with, quoted prices for exchange-traded instruments in active markets. Derivative instruments included in Level 3 are valued using generally unobservable inputs that are based upon the best information available and reflect management’s assumptions about how market participants would price the asset or liability. The Level 3 balances as of December 31, 2018, September 30, 2018, and December 31, 2017, consisted of gas commodity contracts. The Company’s and the Utilities’ policy is to recognize transfers between the levels of the fair value hierarchy, if any, as of the beginning of the interim reporting period in which circumstances change or events occur to cause the transfer. The mutual funds are included in “Other Investments” on the Company’s balance sheets and in “Other Property and Investments” on Spire Missouri’s balance sheets. Derivative assets and liabilities, including receivables and payables associated with cash margin requirements, are presented net in the balance sheets when a legally enforceable netting agreement exists between the Company, Spire Missouri, or Spire Alabama and the counterparty to a derivative contract. Spire Quoted Prices in Active Markets (Level 1) Significant Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Effects of Netting and Cash Margin Receivables /Payables Total As of December 31, 2018 ASSETS Gas Utility: US stock/bond mutual funds $ 18.3 $ — $ — $ — $ 18.3 NYMEX/ICE natural gas contracts 1.2 — — (1.2 ) — Gas Marketing: NYMEX/ICE natural gas contracts 0.2 11.9 — (9.3 ) 2.8 Natural gas commodity contracts — 30.8 — (8.3 ) 22.5 Other: U.S. stock/bond mutual funds 12.5 — — — 12.5 Total $ 32.2 $ 42.7 $ — $ (18.8 ) $ 56.1 LIABILITIES Gas Utility: NYMEX/ICE natural gas contracts $ 0.9 $ — $ — $ (0.9 ) $ — Gas Marketing: NYMEX/ICE natural gas contracts 0.6 8.8 — (9.4 ) — Natural gas commodity contracts — 25.1 0.3 (8.3 ) 17.1 Other: Interest rate swaps — 7.5 — — 7.5 Total $ 1.5 $ 41.4 $ 0.3 $ (18.6 ) $ 24.6 Quoted Prices in Active Markets (Level 1) Significant Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Effects of Netting and Cash Margin Receivables /Payables Total As of September 30, 2018 ASSETS Gas Utility: US stock/bond mutual funds $ 20.3 $ — $ — $ — $ 20.3 NYMEX/ICE natural gas contracts 2.7 — — (2.7 ) — Gas Marketing: NYMEX/ICE natural gas contracts 0.2 4.0 — (4.2 ) — Natural gas commodity contracts — 17.5 — (1.5 ) 16.0 Other: U.S. stock/bond mutual funds 8.9 — — — 8.9 Interest rate swaps — 3.0 — — 3.0 Total $ 32.1 $ 24.5 $ — $ (8.4 ) $ 48.2 LIABILITIES Gas Utility: NYMEX/ICE natural gas contracts $ 1.9 $ — $ — $ (1.9 ) $ — Gas Marketing: NYMEX/ICE natural gas contracts 0.9 10.5 — (11.4 ) — Natural gas commodity contracts — 7.5 0.2 (1.5 ) 6.2 Total $ 2.8 $ 18.0 $ 0.2 $ (14.8 ) $ 6.2 As of December 31, 2017 ASSETS Gas Utility: US stock/bond mutual funds $ 19.5 $ 4.0 $ — $ — $ 23.5 NYMEX/ICE natural gas contracts 0.5 — — (0.5 ) — Gas Marketing: NYMEX/ICE natural gas contracts 2.4 4.0 — (6.1 ) 0.3 Natural gas commodity contracts — 7.7 — (4.3 ) 3.4 Total $ 22.4 $ 15.7 $ — $ (10.9 ) $ 27.2 LIABILITIES Gas Utility: NYMEX/ICE natural gas contracts $ 2.7 $ — $ — $ (2.7 ) $ — Gas Marketing: NYMEX/ICE natural gas contracts 1.1 5.9 — (7.0 ) — Natural gas commodity contracts — 8.9 0.4 (4.3 ) 5.0 Other: Interest rate swaps — 0.8 — — 0.8 Total $ 3.8 $ 15.6 $ 0.4 $ (14.0 ) $ 5.8
Spire Missouri
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Schedule of Fair Value Assets and Liabilities Measured on Recurring Basis	Quoted Prices in Active Markets (Level 1) Significant Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Effects of Netting and Cash Margin Receivables /Payables Total As of December 31, 2018 ASSETS US stock/bond mutual funds $ 18.3 $ — $ — $ — $ 18.3 NYMEX/ICE natural gas contracts 1.2 — — (1.2 ) — Total $ 19.5 $ — $ — $ (1.2 ) $ 18.3 LIABILITIES NYMEX/ICE natural gas contracts $ 0.9 $ — $ — $ (0.9 ) $ — As of September 30, 2018 ASSETS US stock/bond mutual funds $ 20.3 $ — $ — $ — $ 20.3 NYMEX/ICE natural gas contracts 2.7 — — (2.7 ) — Total $ 23.0 $ — $ — $ (2.7 ) $ 20.3 LIABILITIES NYMEX/ICE natural gas contracts $ 1.9 $ — $ — $ (1.9 ) $ — As of December 31, 2017 ASSETS US stock/bond mutual funds $ 19.5 $ 4.0 $ — $ — $ 23.5 NYMEX/ICE natural gas contracts 0.5 — — (0.5 ) — Total $ 20.0 $ 4.0 $ — $ (0.5 ) $ 23.5 LIABILITIES NYMEX/ICE natural gas contracts $ 2.7 $ — $ — $ (2.7 ) $ —

Pension Plans and Other Postr_2

Pension Plans and Other Postretirement Benefits (Tables)	3 Months Ended
	Dec. 31, 2018
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, 2018 2017 Spire Service cost – benefits earned during the period $ 4.8 $ 5.2 Interest cost on projected benefit obligation* 7.1 6.9 Expected return on plan assets* (9.1 ) (9.7 ) Amortization of prior service credit* (0.3 ) (0.3 ) Amortization of actuarial loss* 2.3 3.1 Subtotal 4.8 5.2 Regulatory adjustment 9.9 4.3 Net pension cost $ 14.7 $ 9.5 Spire Missouri Service cost – benefits earned during the period $ 3.1 $ 3.3 Interest cost on projected benefit obligation* 5.0 4.9 Expected return on plan assets* (6.4 ) (7.2 ) Amortization of prior service cost* 0.2 0.2 Amortization of actuarial loss* 2.1 2.6 Subtotal 4.0 3.8 Regulatory adjustment 8.0 2.4 Net pension cost $ 12.0 $ 6.2 Spire Alabama Service cost – benefits earned during the period $ 1.5 $ 1.6 Interest cost on projected benefit obligation* 1.5 1.4 Expected return on plan assets* (1.8 ) (1.7 ) Amortization of prior service credit* (0.4 ) (0.5 ) Amortization of actuarial loss* 0.2 0.5 Subtotal 1.0 1.3 Regulatory adjustment 1.7 1.7 Net pension cost $ 2.7 $ 3.0 * Denotes pension expense line items that are recorded below the operating income line in the income statements, in the line items “Other Income, Net” or “Other (Expense) Income, Net.”
Postretirement Plans
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Net periodic cost	Net periodic postretirement benefit costs consisted of the following components: Three Months Ended December 31, 2018 2017 Spire Service cost – benefits earned during the period $ 1.9 $ 2.3 Interest cost on accumulated postretirement benefit obligation* 2.3 2.2 Expected return on plan assets* (4.1 ) (3.5 ) Amortization of actuarial (gain) loss* (0.1 ) 0.2 Subtotal — 1.2 Regulatory adjustment 2.4 0.1 Net postretirement benefit cost $ 2.4 $ 1.3 Spire Missouri Service cost – benefits earned during the period $ 1.7 $ 2.2 Interest cost on accumulated postretirement benefit obligation* 1.7 1.8 Expected return on plan assets* (2.8 ) (2.4 ) Amortization of prior service cost* 0.1 0.1 Amortization of actuarial (gain) loss* (0.1 ) 0.2 Subtotal 0.6 1.9 Regulatory adjustment 2.9 0.5 Net postretirement benefit cost $ 3.5 $ 2.4 Spire Alabama Service cost – benefits earned during the period $ 0.1 $ — Interest cost on accumulated postretirement benefit obligation* 0.5 0.4 Expected return on plan assets* (1.2 ) (1.0 ) Amortization of prior service credit* (0.1 ) (0.1 ) Subtotal (0.7 ) (0.7 ) Regulatory adjustment (0.5 ) (0.4 ) Net postretirement benefit income $ (1.2 ) $ (1.1 ) * Denotes other postretirement expense line items that are recorded below the operating income line in the income statements, in the line items “Other Income, Net” or “Other (Expense) Income, Net.”

Information by Operating Segm_2

Information by Operating Segment (Tables)	3 Months Ended
	Dec. 31, 2018
Segment Reporting [Abstract]
Schedule of operating segment information	Gas Utility Gas Marketing Other Eliminations Consolidated Three Months Ended December 31, 2018 Operating Revenues: Revenues from external customers $ 573.8 $ 25.8 $ 2.4 $ — $ 602.0 Intersegment revenues 1.4 — 3.0 (4.4 ) — Total Operating Revenues 575.2 25.8 5.4 (4.4 ) 602.0 Operating Expenses: Gas Utility Natural and propane gas 291.8 — — (40.1 ) 251.7 Operation and maintenance 104.9 — — (2.4 ) 102.5 Depreciation and amortization 43.7 — — — 43.7 Taxes, other than income taxes 39.2 — — — 39.2 Total Gas Utility Operating Expenses 479.6 — — (42.5 ) 437.1 Gas Marketing and Other — 13.3 8.4 38.1 59.8 Total Operating Expenses 479.6 13.3 8.4 (4.4 ) 496.9 Operating Income (Loss) $ 95.6 $ 12.5 $ (3.0 ) $ — $ 105.1 Net Economic Earnings (Loss) $ 66.4 $ 8.3 $ (8.8 ) $ — $ 65.9 Gas Utility Gas Marketing Other Eliminations Consolidated Three Months Ended December 31, 2017 Operating Revenues: Revenues from external customers $ 541.9 $ 19.6 $ 0.3 $ — $ 561.8 Intersegment revenues 0.1 — 2.5 (2.6 ) — Total Operating Revenues 542.0 19.6 2.8 (2.6 ) 561.8 Operating Expenses: Gas Utility Natural and propane gas 263.4 — — (22.6 ) 240.8 Operation and maintenance 100.9 — — (1.9 ) 99.0 Depreciation and amortization 40.3 — — — 40.3 Taxes, other than income taxes 36.7 — — — 36.7 Total Gas Utility Operating Expenses 441.3 — — (24.5 ) 416.8 Gas Marketing and Other — 14.6 4.5 21.9 41.0 Total Operating Expenses 441.3 14.6 4.5 (2.6 ) 457.8 Operating Income (Loss) $ 100.7 $ 5.0 $ (1.7 ) $ — $ 104.0 Net Economic Earnings (Loss) $ 59.5 $ 3.6 $ (5.2 ) $ — $ 57.9 December 31, September 30, December 31, 2018 2018 2017 Total Assets: Gas Utility $ 5,843.7 $ 5,606.7 $ 5,611.7 Gas Marketing 416.7 295.3 233.5 Other 2,535.6 2,508.0 2,427.7 Eliminations (1,563.8 ) (1,566.4 ) (1,571.8 ) Total Assets $ 7,232.2 $ 6,843.6 $ 6,701.1
Schedule of reconciliation of consolidated net economic earnings to consolidated net income	The following table reconciles the Company’s net economic earnings to net income. Three Months Ended December 31, 2018 2017 Net Income $ 67.3 $ 116.0 Adjustments, pre-tax: Unrealized (gain) loss on energy-related derivatives (2.2 ) 0.8 Realized gain on economic hedges prior to the sale of the physical commodity — (0.1 ) Acquisition, divestiture and restructuring activities 0.4 1.7 Income tax effect of adjustments 0.4 (0.6 ) Effect of the Tax Cuts and Jobs Act — (59.9 ) Net Economic Earnings $ 65.9 $ 57.9

Summary of Significant Accoun_4

Summary of Significant Accounting Policies - Additional Information (Details) $ in Millions	3 Months Ended			12 Months Ended
	Dec. 31, 2018reporting_unit	Dec. 31, 2018operating-segment	Dec. 31, 2017USD ($)	Sep. 30, 2018USD ($)	Sep. 30, 2017USD ($)	Sep. 30, 2016USD ($)
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Number of operating segments	2	2
ASU 2017-07
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Reclassification of net periodic benefit costs (income) to other income, net			$ (1.1)	$ 14.4	$ 19.2	$ 9.6
Spire Missouri | ASU 2017-07
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Reclassification of net periodic benefit costs (income) to other income, net			0.2	17.2	17.2	11.2
Spire Alabama | ASU 2017-07
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Reclassification of net periodic benefit costs (income) to other income, net			$ (1)	$ (2)	$ 2.2	$ (1.6)

Summary of Significant Accoun_5

Summary of Significant Accounting Policies - Schedule of Inter-company Transactions (Details) - Affiliated Entity - Spire Missouri - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Spire Marketing | Regulated Operation
Related Party Transaction [Line Items]
Purchases of natural gas from Spire Marketing	$ 39.8	$ 22.3
Sales of natural gas to Spire Marketing	1.4	0.1
Spire NGL Inc. | Unregulated Operation
Related Party Transaction [Line Items]
Transportation services received from Spire NGL Inc.	$ 0.3	$ 0.3

Summary of Significant Accoun_6

Summary of Significant Accounting Policies - Accrued Capital Expenditures (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Sep. 30, 2018
Schedule Of Accrued Capital Expenditures Excluded From Statement Of Cash Flow [Line Items]
Accruals for capital expenditures	$ 46.2	$ 31.8	$ 62.1
Spire Missouri
Schedule Of Accrued Capital Expenditures Excluded From Statement Of Cash Flow [Line Items]
Accruals for capital expenditures	18.1	15.2	36.7
Spire Alabama
Schedule Of Accrued Capital Expenditures Excluded From Statement Of Cash Flow [Line Items]
Accruals for capital expenditures	$ 9.7	$ 7	$ 8.9

Revenue - Schedule of Revenue D

Revenue - Schedule of Revenue Disaggregated by Source and Customer Type (Details) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Disaggregation Of Revenue [Line Items]
Total operating revenues	$ 573.8	$ 541.9
Total operating revenues	28.2	19.9
Total operating revenues	602	561.8
Intersegment Eliminations
Disaggregation Of Revenue [Line Items]
Total operating revenues	(4.4)	(2.6)
Gas Utility
Disaggregation Of Revenue [Line Items]
Total operating revenues	573.8	541.9
Gas Utility | Operating Segments
Disaggregation Of Revenue [Line Items]
Total operating revenues	575.2	542
Gas Utility | Intersegment Eliminations
Disaggregation Of Revenue [Line Items]
Total operating revenues	1.4	0.1
Gas Marketing
Disaggregation Of Revenue [Line Items]
Total operating revenues	25.8	19.6
Gas Marketing | Operating Segments
Disaggregation Of Revenue [Line Items]
Total operating revenues	25.8	19.6
Gas Marketing | Intersegment Eliminations
Disaggregation Of Revenue [Line Items]
Total operating revenues	0	$ 0
Spire
Disaggregation Of Revenue [Line Items]
Total operating revenues	602
Spire | Operating Segments
Disaggregation Of Revenue [Line Items]
Total operating revenues	606.4
Spire | Intersegment Eliminations
Disaggregation Of Revenue [Line Items]
Total operating revenues	(4.4)
Spire | Gas Utility | Operating Segments
Disaggregation Of Revenue [Line Items]
Total operating revenues	581
Changes in accrued revenue under alternative revenue programs	(5.8)
Total operating revenues	575.2
Spire | Gas Utility | Operating Segments | Residential
Disaggregation Of Revenue [Line Items]
Total operating revenues	393.6
Spire | Gas Utility | Operating Segments | Commercial & Industrial
Disaggregation Of Revenue [Line Items]
Total operating revenues	130.3
Spire | Gas Utility | Operating Segments | Transportation
Disaggregation Of Revenue [Line Items]
Total operating revenues	29.5
Spire | Gas Utility | Operating Segments | Off-system & Other Incentive
Disaggregation Of Revenue [Line Items]
Total operating revenues	14.9
Spire | Gas Utility | Operating Segments | Other Customer Revenue
Disaggregation Of Revenue [Line Items]
Total operating revenues	12.7
Spire | Gas Marketing | Operating Segments
Disaggregation Of Revenue [Line Items]
Total operating revenues	25.8
Spire | Gas Marketing | Operating Segments | Revenue From Contracts With Retail Customers
Disaggregation Of Revenue [Line Items]
Total operating revenues	25.8
Spire | Other | Operating Segments
Disaggregation Of Revenue [Line Items]
Total operating revenues	$ 5.4

Revenue - Schedule of Operating

Revenue - Schedule of Operating Revenue Information (Details) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Disaggregation Of Revenue [Line Items]
Total Operating Revenues	$ 602	$ 561.8
Spire Missouri
Disaggregation Of Revenue [Line Items]
Total operating revenues	417.7
Changes in accrued revenue under alternative revenue programs	(4.5)
Total Operating Revenues	413.2	392.3
Spire Missouri | Residential
Disaggregation Of Revenue [Line Items]
Total operating revenues	302.1
Spire Missouri | Commercial & Industrial
Disaggregation Of Revenue [Line Items]
Total operating revenues	89.1
Spire Missouri | Transportation
Disaggregation Of Revenue [Line Items]
Total operating revenues	9
Spire Missouri | Off-system & Other Incentive
Disaggregation Of Revenue [Line Items]
Total operating revenues	14.9
Spire Missouri | Other Customer Revenue
Disaggregation Of Revenue [Line Items]
Total operating revenues	2.6
Spire Alabama
Disaggregation Of Revenue [Line Items]
Total operating revenues	134.6
Changes in accrued revenue under alternative revenue programs	(1.1)
Total Operating Revenues	133.5	$ 120.8
Spire Alabama | Residential
Disaggregation Of Revenue [Line Items]
Total operating revenues	75.4
Spire Alabama | Commercial & Industrial
Disaggregation Of Revenue [Line Items]
Total operating revenues	31.4
Spire Alabama | Transportation
Disaggregation Of Revenue [Line Items]
Total operating revenues	18.2
Spire Alabama | Other Customer Revenue
Disaggregation Of Revenue [Line Items]
Total operating revenues	$ 9.6

Revenue - Additional Informatio

Revenue - Additional Information (Details)	3 Months Ended
	Dec. 31, 2018
Revenue Recognition [Line Items]
Remaining performance obligation, practical expedient	true
Maximum
Revenue Recognition [Line Items]
Revenue remaining performance obligation original excepted duration	1 year

Revenue - Schedule of Gross Rec

Revenue - Schedule of Gross Receipts Taxes Recorded Revenues (Details) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Scheduleof Gross Receipts Taxes [Line Items]
Gross receipts taxes recorded in regulated gas distribution operating revenues	$ 25.9	$ 23.1
Spire Missouri
Scheduleof Gross Receipts Taxes [Line Items]
Gross receipts taxes recorded in regulated gas distribution operating revenues	18.5	16.2
Spire Alabama
Scheduleof Gross Receipts Taxes [Line Items]
Gross receipts taxes recorded in regulated gas distribution operating revenues	$ 6.3	$ 5.6

Earnings Per Share - Schedule o

Earnings Per Share - Schedule of Basic and Diluted Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Basic Earnings Per Share:
Net Income	$ 67.3	$ 116
Less: Income allocated to participating securities	0.1	0.2
Income Available to Common Shareholders	$ 67.2	$ 115.8
Weighted Average Shares Outstanding (in millions)	50.6	48.2
Basic Earnings Per Share	$ 1.33	$ 2.40
Diluted Earnings Per Share:
Net Income	$ 67.3	$ 116
Less: Income allocated to participating securities	0.1	0.2
Income Available to Common Shareholders	$ 67.2	$ 115.8
Weighted Average Shares Outstanding (in millions)	50.6	48.2
Dilutive Effect of Restricted Stock and Restricted Stock Units (in millions)	0.2	0.2
Weighted Average Diluted Shares (in millions)	50.8	48.4
Diluted Earnings Per Share	$ 1.32	$ 2.39

Earnings Per Share - Schedule_2

Earnings Per Share - Schedule of Basic and Diluted Earnings Per Share (Parenthetical) (Details) - shares shares in Millions	3 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Restricted Stock and Restricted Stock Units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Outstanding shares excluded from calculation of diluted EPS (in shares)	0.4	0.3

Regulatory Matters - Schedule o

Regulatory Matters - Schedule of Regulatory Assets and Liabilities, Including Purchased Gas Adjustments, Reflected in Balance Sheets (Details) - USD ($) $ in Millions	Dec. 31, 2018	Sep. 30, 2018	Dec. 31, 2017
Regulatory Asset And Liabilities [Line Items]
Regulatory assets, current	$ 63.4	$ 72.8	$ 149.3
Regulatory assets, non current	655.1	669.8	716.6
Total Regulatory Assets	718.5	742.6	865.9
Regulatory liabilities, current	37	35.7	21.5
Regulatory liabilities, non current	363.4	354.6	335.1
Total Regulatory Liabilities	400.4	390.3	356.6
Spire Missouri
Regulatory Asset And Liabilities [Line Items]
Regulatory assets, current	29.7	30.7	76.7
Regulatory assets, non current	427.6	441.1	484.1
Total Regulatory Assets	457.3	471.8	560.8
Regulatory liabilities, current	20.6	16.7	2.7
Regulatory liabilities, non current	279.7	274.9	241.2
Total Regulatory Liabilities	300.3	291.6	243.9
Spire Alabama
Regulatory Asset And Liabilities [Line Items]
Regulatory assets, current	18.8	26.2	58
Regulatory assets, non current	200.2	201.5	197.4
Total Regulatory Assets	219	227.7	255.4
Regulatory liabilities, current	10.2	7.6	11.3
Regulatory liabilities, non current	30.6	31.3	39
Total Regulatory Liabilities	40.8	38.9	50.3
Pension and Postretirement Benefit Costs
Regulatory Asset And Liabilities [Line Items]
Regulatory assets, current	30.2	30.2	43
Regulatory assets, non current	350	364.9	394.8
Pension and Postretirement Benefit Costs | Spire Missouri
Regulatory Asset And Liabilities [Line Items]
Regulatory assets, current	21.9	21.9	34.9
Regulatory assets, non current	279.8	292.5	315.8
Pension and Postretirement Benefit Costs | Spire Alabama
Regulatory Asset And Liabilities [Line Items]
Regulatory assets, current	7.3	7.3	7.2
Regulatory assets, non current	63	64.8	70.8
Unamortized Purchased Gas Adjustments
Regulatory Asset And Liabilities [Line Items]
Regulatory assets, current	3	8.2	77.9
Unamortized Purchased Gas Adjustments | Spire Missouri
Regulatory Asset And Liabilities [Line Items]
Regulatory assets, current		1	38.5
Unamortized Purchased Gas Adjustments | Spire Alabama
Regulatory Asset And Liabilities [Line Items]
Regulatory assets, current	1.6	6.4	39.4
Other
Regulatory Asset And Liabilities [Line Items]
Regulatory assets, current	30.2	34.4	28.4
Regulatory assets, non current	38.4	42.4	54.8
Other | Spire Missouri
Regulatory Asset And Liabilities [Line Items]
Regulatory assets, current	7.8	7.8	3.3
Regulatory assets, non current	17.5	21.4	25.2
Other | Spire Alabama
Regulatory Asset And Liabilities [Line Items]
Regulatory assets, current	9.9	12.5	11.4
Regulatory assets, non current	3.2	3.3	2.7
Future Income Taxes Due from Customers
Regulatory Asset And Liabilities [Line Items]
Regulatory assets, non current	99.1	96.3	113.1
Future Income Taxes Due from Customers | Spire Missouri
Regulatory Asset And Liabilities [Line Items]
Regulatory assets, non current	96.7	94.4	113.1
Accrued Cost of Removal
Regulatory Asset And Liabilities [Line Items]
Regulatory assets, non current	134	133.4	123.9
Accrued Cost of Removal | Spire Alabama
Regulatory Asset And Liabilities [Line Items]
Regulatory assets, non current	134	133.4	123.9
Energy Efficiency
Regulatory Asset And Liabilities [Line Items]
Regulatory assets, non current	33.6	32.8	30
Energy Efficiency | Spire Missouri
Regulatory Asset And Liabilities [Line Items]
Regulatory assets, non current	33.6	32.8	30
Rate Stabilization and Equalization ("RSE") Adjustment
Regulatory Asset And Liabilities [Line Items]
Regulatory liabilities, current	2.5	0	1
Rate Stabilization and Equalization ("RSE") Adjustment | Spire Alabama
Regulatory Asset And Liabilities [Line Items]
Regulatory liabilities, current	2.5	0	1
Refundable Negative Salvage
Regulatory Asset And Liabilities [Line Items]
Regulatory liabilities, current	4.6	5.2	7.9
Regulatory liabilities, non current		0	3.8
Refundable Negative Salvage | Spire Alabama
Regulatory Asset And Liabilities [Line Items]
Regulatory liabilities, current	4.6	5.2	7.9
Regulatory liabilities, non current		0	3.9
Unamortized Purchased Gas Adjustments
Regulatory Asset And Liabilities [Line Items]
Regulatory liabilities, current	6.1	2.9	1
Regulatory liabilities, non current	16.7	4.7	6.5
Unamortized Purchased Gas Adjustments | Spire Missouri
Regulatory Asset And Liabilities [Line Items]
Regulatory liabilities, current	5.8	1.9	0
Regulatory liabilities, non current	16.7	4.7	6.5
Other
Regulatory Asset And Liabilities [Line Items]
Regulatory liabilities, current	23.8	27.6	11.6
Regulatory liabilities, non current	90.4	80.2	34.2
Other | Spire Missouri
Regulatory Asset And Liabilities [Line Items]
Regulatory liabilities, current	14.8	14.8	2.7
Regulatory liabilities, non current	75.4	69.3	23.5
Other | Spire Alabama
Regulatory Asset And Liabilities [Line Items]
Regulatory liabilities, current	3.1	2.4	2.4
Regulatory liabilities, non current	3.5	3.5	3.6
Deferred Taxes Due to Customers
Regulatory Asset And Liabilities [Line Items]
Regulatory liabilities, non current	169.8	178.3	177.4
Deferred Taxes Due to Customers | Spire Missouri
Regulatory Asset And Liabilities [Line Items]
Regulatory liabilities, non current	152.4	161.1	159.2
Pension and Postretirement Benefit Costs
Regulatory Asset And Liabilities [Line Items]
Regulatory liabilities, non current	27.1	27.8	31.5
Pension and Postretirement Benefit Costs | Spire Alabama
Regulatory Asset And Liabilities [Line Items]
Regulatory liabilities, non current	27.1	27.8	31.5
Accrued Cost of Removal
Regulatory Asset And Liabilities [Line Items]
Regulatory liabilities, non current	59.4	63.6	81.7
Accrued Cost of Removal | Spire Missouri
Regulatory Asset And Liabilities [Line Items]
Regulatory liabilities, non current	$ 35.2	$ 39.8	$ 52

Regulatory Matters - Schedule_2

Regulatory Matters - Schedule of Regulatory Assets Not Earning a Return (Details) - USD ($) $ in Millions	Dec. 31, 2018	Sep. 30, 2018	Dec. 31, 2017
Regulatory Assets [Line Items]
Total Regulatory Assets Not Earning a Return	$ 254.6	$ 259.8	$ 318.1
Pension and Postretirement Benefit Costs
Regulatory Assets [Line Items]
Total Regulatory Assets Not Earning a Return	141.2	148.4	193.8
Future Income Taxes Due from Customers
Regulatory Assets [Line Items]
Total Regulatory Assets Not Earning a Return	99.1	96.3	113.1
Other
Regulatory Assets [Line Items]
Total Regulatory Assets Not Earning a Return	14.3	15.1	11.2
Spire Missouri
Regulatory Assets [Line Items]
Total Regulatory Assets Not Earning a Return	252.2	257.9	318.1
Spire Missouri | Pension and Postretirement Benefit Costs
Regulatory Assets [Line Items]
Total Regulatory Assets Not Earning a Return	141.2	148.4	193.8
Spire Missouri | Future Income Taxes Due from Customers
Regulatory Assets [Line Items]
Total Regulatory Assets Not Earning a Return	96.7	94.4	113.1
Spire Missouri | Other
Regulatory Assets [Line Items]
Total Regulatory Assets Not Earning a Return	$ 14.3	$ 15.1	$ 11.2

Regulatory Matters - Additional

Regulatory Matters - Additional Information (Details) - USD ($) $ in Millions	Jan. 14, 2019	Nov. 30, 2018	Sep. 28, 2018	Apr. 25, 2018	Dec. 31, 2018	Jan. 31, 2019
Public Utilities, General Disclosures [Line Items]
Remaining recovery period for certain regulatory assets for which no return on investment during recovery period is provided (in years)					20 years
Remaining recovery period for regulatory assets for which no return on investment during recovery period is provided (in years)					15 years
Spire Missouri
Public Utilities, General Disclosures [Line Items]
Public utilities, requested rate increase (decrease), amount					$ 1.7
Public utilities, requested rate increase (decrease), percentage					51.00%
Spire Alabama
Public Utilities, General Disclosures [Line Items]
Approved rate increase (decrease) amount					$ (4.1)
Public utilities, requested rate increase (decrease), amount		$ 8.7
Infrastructure System Replacement Surcharge | Spire Missouri East
Public Utilities, General Disclosures [Line Items]
Approved rate increase (decrease) amount			$ 2.6
Infrastructure System Replacement Surcharge | Spire Missouri East | Subsequent Event
Public Utilities, General Disclosures [Line Items]
Applications requests for the approval of revenue related to commission amount						$ 7.4
Infrastructure System Replacement Surcharge | Spire Missouri West
Public Utilities, General Disclosures [Line Items]
Approved rate increase (decrease) amount			$ 5.4
Infrastructure System Replacement Surcharge | Spire Missouri West | Subsequent Event
Public Utilities, General Disclosures [Line Items]
Applications requests for the approval of revenue related to commission amount						$ 8.4
Infrastructure System Replacement Surcharge | Spire Missouri | Subsequent Event
Public Utilities, General Disclosures [Line Items]
Public utilities, requested rate increase (decrease), amount	$ 3.2
Infrastructure System Replacement Surcharge | MoPSC
Public Utilities, General Disclosures [Line Items]
Approved rate increase (decrease), costs from buildings sold in 2014 excluded from rate base				$ 1.8
Rate case expenses				0.9
Pension Cost | Infrastructure System Replacement Surcharge | MoPSC
Public Utilities, General Disclosures [Line Items]
Regulatory assets recovery				$ 28.8

Financing Arrangements and Lo_3

Financing Arrangements and Long-term Debt - Additional Information (Details)	1 Months Ended		3 Months Ended
	Dec. 31, 2018USD ($)	Oct. 31, 2018USD ($)	Dec. 31, 2018USD ($)	Jan. 15, 2019USD ($)	Sep. 30, 2018USD ($)	Dec. 31, 2017USD ($)	Dec. 14, 2016bank
Line of Credit Facility [Line Items]
Line of credit facility borrowing capacity	$ 975,000,000		$ 975,000,000
Credit facility borrowings	0		0		$ 0	$ 0
Non-interest-bearing Note
Line of Credit Facility [Line Items]
Settlement of debt		$ 10,000,000
Term Loan
Line of Credit Facility [Line Items]
Long-term Debt	$ 100,000,000		100,000,000
Debt instrument, maturity date	Dec. 1, 2021
Liabilities | Lender Concentration Risk
Line of Credit Facility [Line Items]
Line of credit facility, number of banks in agreement | bank							11
Spire
Line of Credit Facility [Line Items]
Line of credit facility borrowing capacity	$ 300,000,000		300,000,000
Short-term borrowings used to support lending to Utilities	509,900,000		509,900,000
Spire Missouri
Line of Credit Facility [Line Items]
Line of credit facility borrowing capacity	475,000,000		475,000,000
Spire Alabama
Line of Credit Facility [Line Items]
Line of credit facility borrowing capacity	$ 200,000,000		$ 200,000,000
Spire Alabama | Senior Notes | Subsequent Event | Private Placement | Series 2019 A senior notes due 2049
Line of Credit Facility [Line Items]
Long-term debt				$ 90,000,000
Stated interest rate				4.64%
Line of Credit
Line of Credit Facility [Line Items]
Minimum required ratio of earnings before interest, taxes, depreciation, and amortization (EBITDA) times interest expense as required by the line of credit covenant	70.00%		70.00%
Debt to total capitalization ratio	0.55		0.55
Line of Credit | Spire Missouri
Line of Credit Facility [Line Items]
Debt to total capitalization ratio	0.50		0.50
Line of Credit | Spire Alabama
Line of Credit Facility [Line Items]
Debt to total capitalization ratio	0.38		0.38
Commercial Paper Notes
Line of Credit Facility [Line Items]
Long-term debt	$ 975,000,000		$ 975,000,000
Debt term			365 days

Financing Arrangements and Lo_4

Financing Arrangements and Long-term Debt - Schedule of Spire Missouri and Alabama Short-term Borrowings (Details) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Dec. 31, 2017
Spire Missouri | Borrowings
Short-term Debt [Line Items]
Weighted average borrowings outstanding	$ 343.9
Weighted average interest rate	2.70%
Minimum borrowing outstanding	$ 273.6
Maximum borrowing outstanding	404.9
Borrowings outstanding	$ 308	$ 345.3	$ 275.6
Weighted average interest rate	3.10%	2.30%	2.00%
Spire Alabama | Borrowings
Short-term Debt [Line Items]
Weighted average borrowings outstanding	$ 152.3
Weighted average interest rate	2.70%
Minimum borrowing outstanding	$ 140.8
Maximum borrowing outstanding	169.2
Borrowings outstanding	$ 164.2	$ 142.5	$ 163.1
Weighted average interest rate	3.10%	2.30%	2.00%
Spire | Commercial Paper Notes
Short-term Debt [Line Items]
Weighted average borrowings outstanding	$ 622.9
Weighted average interest rate	2.70%
Minimum borrowing outstanding	$ 562.3
Maximum borrowing outstanding	689.3
Borrowings outstanding	$ 626.1	$ 553.6	$ 583.6
Weighted average interest rate	3.10%	2.40%	2.00%

Financing Arrangements and Lo_5

Financing Arrangements and Long-term Debt - Summary of Net of Capitalized Interest (Details) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Spire
Line of Credit Facility [Line Items]
Interest expense, net	$ 1.2	$ 0.4
Spire Missouri
Line of Credit Facility [Line Items]
Interest expense, net	$ 0.5	$ 0.2

Fair Value of Financial Instr_3

Fair Value of Financial Instruments - Summary of Financial Instruments Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Millions	Dec. 31, 2018	Sep. 30, 2018	Dec. 31, 2017
Quoted Prices in Active Markets (Level 1)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	$ 8.4	$ 4.4	$ 6.7
Quoted Prices in Active Markets (Level 1) | Spire Missouri
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	4.9	2	4.1
Significant Observable Inputs (Level 2)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Short-term debt	626.1	553.6	583.6
Long-term debt, including current portion	2,133.9	2,074	2,280.1
Significant Observable Inputs (Level 2) | Spire Missouri
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Short-term debt	308	345.3	275.6
Long-term debt, including current portion	997.3	906.6	1,068.6
Significant Observable Inputs (Level 2) | Spire Alabama
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Short-term debt	164.2	142.5	163.1
Long-term debt, including current portion	311.3	321.7	303.5
Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	8.4	4.4	6.7
Short-term debt	626.1	553.6	583.6
Long-term debt, including current portion	2,167	2,075.6	2,135.5
Carrying Amount | Spire Missouri
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	4.9	2	4.1
Short-term debt	308	345.3	275.6
Long-term debt, including current portion	974.5	874.4	974.1
Carrying Amount | Spire Alabama
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Short-term debt	164.2	142.5	163.1
Long-term debt, including current portion	322.6	322.6	277.8
Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	8.4	4.4	6.7
Short-term debt	626.1	553.6	583.6
Long-term debt, including current portion	2,133.9	2,074	2,280.1
Fair Value | Spire Missouri
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	4.9	2	4.1
Short-term debt	308	345.3	275.6
Long-term debt, including current portion	997.3	906.6	1,068.6
Fair Value | Spire Alabama
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Short-term debt	164.2	142.5	163.1
Long-term debt, including current portion	$ 311.3	$ 321.7	$ 303.5

Fair Value Measurements - Sched

Fair Value Measurements - Schedule of Fair Value Assets and Liabilities Measured on Recurring Basis (Details) - Fair Value, Measurements, Recurring - USD ($) $ in Millions	Dec. 31, 2018	Sep. 30, 2018	Dec. 31, 2017
ASSETS
Effects of netting and cash margin receivables/payables	$ (18.8)	$ (8.4)	$ (10.9)
Derivative asset after the effects of netting	56.1	48.2	27.2
LIABILITIES
Effects of netting and cash margin receivables/payables	(18.6)	(14.8)	(14)
Derivative liability after the effects of netting	24.6	6.2	5.8
Spire Missouri
ASSETS
Effects of netting and cash margin receivables/payables	(1.2)	(2.7)	(0.5)
Derivative asset after the effects of netting	18.3	20.3	23.5
US stock/bond mutual funds | Spire Missouri
ASSETS
Effects of netting and cash margin receivables/payables	0	0	0
Derivative asset after the effects of netting	18.3	20.3	23.5
NYMEX/ICE natural gas contracts | Spire Missouri
ASSETS
Effects of netting and cash margin receivables/payables	(1.2)	(2.7)	(0.5)
Derivative asset after the effects of netting	0	0	0
LIABILITIES
Effects of netting and cash margin receivables/payables	(0.9)	(1.9)	(2.7)
Derivative liability after the effects of netting	0	0	0
Quoted Prices in Active Markets (Level 1)
ASSETS
Derivative asset before effects of netting	32.2	32.1	22.4
LIABILITIES
Derivative liability before effects of netting	1.5	2.8	3.8
Quoted Prices in Active Markets (Level 1) | Spire Missouri
ASSETS
Derivative asset before effects of netting	19.5	23	20
Quoted Prices in Active Markets (Level 1) | US stock/bond mutual funds | Spire Missouri
ASSETS
Derivative asset before effects of netting	18.3	20.3	19.5
Quoted Prices in Active Markets (Level 1) | NYMEX/ICE natural gas contracts | Spire Missouri
ASSETS
Derivative asset before effects of netting	1.2	2.7	0.5
LIABILITIES
Derivative liability before effects of netting	0.9	1.9	2.7
Significant Observable Inputs (Level 2)
ASSETS
Derivative asset before effects of netting	42.7	24.5	15.7
LIABILITIES
Derivative liability before effects of netting	41.4	18	15.6
Significant Observable Inputs (Level 2) | Spire Missouri
ASSETS
Derivative asset before effects of netting	0	0	4
Significant Observable Inputs (Level 2) | US stock/bond mutual funds | Spire Missouri
ASSETS
Derivative asset before effects of netting	0	0	4
Significant Observable Inputs (Level 2) | NYMEX/ICE natural gas contracts | Spire Missouri
ASSETS
Derivative asset before effects of netting	0	0	0
LIABILITIES
Derivative liability before effects of netting	0	0	0
Significant Unobservable Inputs (Level 3)
ASSETS
Derivative asset before effects of netting	0	0	0
LIABILITIES
Derivative liability before effects of netting	0.3	0.2	0.4
Significant Unobservable Inputs (Level 3) | Spire Missouri
ASSETS
Derivative asset before effects of netting	0	0	0
Significant Unobservable Inputs (Level 3) | US stock/bond mutual funds | Spire Missouri
ASSETS
Derivative asset before effects of netting	0	0	0
Significant Unobservable Inputs (Level 3) | NYMEX/ICE natural gas contracts | Spire Missouri
ASSETS
Derivative asset before effects of netting	0	0	0
LIABILITIES
Derivative liability before effects of netting	0	0	0
Corporate, Non-Segment | US stock/bond mutual funds
ASSETS
Effects of netting and cash margin receivables/payables	0	0
Derivative asset after the effects of netting	12.5	8.9
Corporate, Non-Segment | Interest rate swaps
ASSETS
Effects of netting and cash margin receivables/payables		0
Derivative asset after the effects of netting		3
LIABILITIES
Effects of netting and cash margin receivables/payables	0		0
Derivative liability after the effects of netting	7.5		0.8
Corporate, Non-Segment | Quoted Prices in Active Markets (Level 1) | US stock/bond mutual funds
ASSETS
Derivative asset before effects of netting	12.5	8.9
Corporate, Non-Segment | Quoted Prices in Active Markets (Level 1) | Interest rate swaps
ASSETS
Derivative asset before effects of netting		0
LIABILITIES
Derivative liability before effects of netting	0		0
Corporate, Non-Segment | Significant Observable Inputs (Level 2) | US stock/bond mutual funds
ASSETS
Derivative asset before effects of netting	0	0
Corporate, Non-Segment | Significant Observable Inputs (Level 2) | Interest rate swaps
ASSETS
Derivative asset before effects of netting		3
LIABILITIES
Derivative liability before effects of netting	7.5		0.8
Corporate, Non-Segment | Significant Unobservable Inputs (Level 3) | US stock/bond mutual funds
ASSETS
Derivative asset before effects of netting	0	0
Corporate, Non-Segment | Significant Unobservable Inputs (Level 3) | Interest rate swaps
ASSETS
Derivative asset before effects of netting		0
LIABILITIES
Derivative liability before effects of netting	0		0
Gas Utility | Operating Segments | US stock/bond mutual funds
ASSETS
Effects of netting and cash margin receivables/payables	0	0	0
Derivative asset after the effects of netting	18.3	20.3	23.5
Gas Utility | Operating Segments | NYMEX/ICE natural gas contracts
ASSETS
Effects of netting and cash margin receivables/payables	(1.2)	(2.7)	(0.5)
Derivative asset after the effects of netting	0	0	0
LIABILITIES
Effects of netting and cash margin receivables/payables	(0.9)	(1.9)	(2.7)
Derivative liability after the effects of netting	0	0	0
Gas Utility | Operating Segments | Quoted Prices in Active Markets (Level 1) | US stock/bond mutual funds
ASSETS
Derivative asset before effects of netting	18.3	20.3	19.5
Gas Utility | Operating Segments | Quoted Prices in Active Markets (Level 1) | NYMEX/ICE natural gas contracts
ASSETS
Derivative asset before effects of netting	1.2	2.7	0.5
LIABILITIES
Derivative liability before effects of netting	0.9	1.9	2.7
Gas Utility | Operating Segments | Significant Observable Inputs (Level 2) | US stock/bond mutual funds
ASSETS
Derivative asset before effects of netting	0	0	4
Gas Utility | Operating Segments | Significant Observable Inputs (Level 2) | NYMEX/ICE natural gas contracts
ASSETS
Derivative asset before effects of netting	0	0	0
LIABILITIES
Derivative liability before effects of netting	0	0	0
Gas Utility | Operating Segments | Significant Unobservable Inputs (Level 3) | US stock/bond mutual funds
ASSETS
Derivative asset before effects of netting	0	0	0
Gas Utility | Operating Segments | Significant Unobservable Inputs (Level 3) | NYMEX/ICE natural gas contracts
ASSETS
Derivative asset before effects of netting	0	0	0
LIABILITIES
Derivative liability before effects of netting	0	0	0
Gas Marketing | Operating Segments | NYMEX/ICE natural gas contracts
ASSETS
Effects of netting and cash margin receivables/payables	(9.3)	(4.2)	(6.1)
Derivative asset after the effects of netting	2.8	0	0.3
LIABILITIES
Effects of netting and cash margin receivables/payables	(9.4)	(11.4)	(7)
Derivative liability after the effects of netting	0	0	0
Gas Marketing | Operating Segments | Natural gas commodity contracts
ASSETS
Effects of netting and cash margin receivables/payables	(8.3)	(1.5)	(4.3)
Derivative asset after the effects of netting	22.5	16	3.4
LIABILITIES
Effects of netting and cash margin receivables/payables	(8.3)	(1.5)	(4.3)
Derivative liability after the effects of netting	17.1	6.2	5
Gas Marketing | Operating Segments | Quoted Prices in Active Markets (Level 1) | NYMEX/ICE natural gas contracts
ASSETS
Derivative asset before effects of netting	0.2	0.2	2.4
LIABILITIES
Derivative liability before effects of netting	0.6	0.9	1.1
Gas Marketing | Operating Segments | Quoted Prices in Active Markets (Level 1) | Natural gas commodity contracts
ASSETS
Derivative asset before effects of netting	0	0	0
LIABILITIES
Derivative liability before effects of netting	0	0	0
Gas Marketing | Operating Segments | Significant Observable Inputs (Level 2) | NYMEX/ICE natural gas contracts
ASSETS
Derivative asset before effects of netting	11.9	4	4
LIABILITIES
Derivative liability before effects of netting	8.8	10.5	5.9
Gas Marketing | Operating Segments | Significant Observable Inputs (Level 2) | Natural gas commodity contracts
ASSETS
Derivative asset before effects of netting	30.8	17.5	7.7
LIABILITIES
Derivative liability before effects of netting	25.1	7.5	8.9
Gas Marketing | Operating Segments | Significant Unobservable Inputs (Level 3) | NYMEX/ICE natural gas contracts
ASSETS
Derivative asset before effects of netting	0	0	0
LIABILITIES
Derivative liability before effects of netting	0	0	0
Gas Marketing | Operating Segments | Significant Unobservable Inputs (Level 3) | Natural gas commodity contracts
ASSETS
Derivative asset before effects of netting	0	0	0
LIABILITIES
Derivative liability before effects of netting	$ 0.3	$ 0.2	$ 0.4

Fair Value Measurements - Addit

Fair Value Measurements - Additional Information (Details) - USD ($)	Dec. 31, 2018	Sep. 30, 2018	Dec. 31, 2017
Spire Alabama
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Outstanding derivative contracts	$ 0	$ 0	$ 0

Concentration of Credit Risk -

Concentration of Credit Risk - Additional Information (Details) $ in Millions	3 Months Ended
	Dec. 31, 2018USD ($)subsegmentcounterparty
Concentration Risk [Line Items]
Number of groups with potential to affect overall exposure | subsegment	3
Number of large counterparties for which credit risk is disclosed | counterparty	5
Number of counterparties with investment-grade rating | counterparty	4
Energy Producers And Their Affiliates
Concentration Risk [Line Items]
Accounts receivable	$ 26
Net receivable amount	13.2
Utility Companies And Their Affiliates
Concentration Risk [Line Items]
Accounts receivable	121.9
Net receivable amount	102.5
Five Largest Counterparties
Concentration Risk [Line Items]
Accounts receivable	41.8
Net receivable amount	$ 35

Pension Plans and Other Postr_3

Pension Plans and Other Postretirement Benefits - Schedule of Net Periodic Cost (Details) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Pension Plans
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost – benefits earned during the period	$ 4.8	$ 5.2
Interest cost on projected benefit obligation	7.1	6.9
Expected return on plan assets	(9.1)	(9.7)
Amortization of prior service cost (credit)	(0.3)	(0.3)
Amortization of actuarial (gain) loss	2.3	3.1
Subtotal	4.8	5.2
Regulatory adjustment	9.9	4.3
Net pension cost	14.7	9.5
Postretirement Plans
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost – benefits earned during the period	1.9	2.3
Interest cost on projected benefit obligation	2.3	2.2
Expected return on plan assets	(4.1)	(3.5)
Amortization of actuarial (gain) loss	(0.1)	0.2
Subtotal		1.2
Regulatory adjustment	2.4	0.1
Net pension cost	2.4	1.3
Spire Missouri | Pension Plans
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost – benefits earned during the period	3.1	3.3
Interest cost on projected benefit obligation	5	4.9
Expected return on plan assets	(6.4)	(7.2)
Amortization of prior service cost (credit)	0.2	0.2
Amortization of actuarial (gain) loss	2.1	2.6
Subtotal	4	3.8
Regulatory adjustment	8	2.4
Net pension cost	12	6.2
Spire Missouri | Postretirement Plans
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost – benefits earned during the period	1.7	2.2
Interest cost on projected benefit obligation	1.7	1.8
Expected return on plan assets	(2.8)	(2.4)
Amortization of prior service cost (credit)	0.1	0.1
Subtotal	0.6	1.9
Regulatory adjustment	2.9	0.5
Net pension cost	3.5	2.4
Spire Alabama | Pension Plans
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost – benefits earned during the period	1.5	1.6
Interest cost on projected benefit obligation	1.5	1.4
Expected return on plan assets	(1.8)	(1.7)
Amortization of prior service cost (credit)	(0.4)	(0.5)
Amortization of actuarial (gain) loss	0.2	0.5
Subtotal	1	1.3
Regulatory adjustment	1.7	1.7
Net pension cost	2.7	3
Spire Alabama | Postretirement Plans
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost – benefits earned during the period	0.1
Interest cost on projected benefit obligation	0.5	0.4
Expected return on plan assets	(1.2)	(1)
Amortization of prior service cost (credit)	(0.1)	(0.1)
Subtotal	(0.7)	(0.7)
Regulatory adjustment	(0.5)	(0.4)
Net pension cost	$ (1.2)	$ (1.1)

Pension Plans and Other Postr_4

Pension Plans and Other Postretirement Benefits - Additional Information (Details)	3 Months Ended
	Dec. 31, 2018USD ($)
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Anticipated Contributions to pension plans for qualified trust	$ 1,400,000
Anticipated contributions to pension plans for non-qualified plans	$ 0
Medical insurance available until age is reached after early retirement	65 years
Pension Plans | Spire Missouri
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Anticipated Contributions to pension plans for qualified trust	$ 25,300,000
Postretirement Plans | Spire Alabama
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Anticipated Contributions to pension plans for qualified trust	0
Employer contributions	0
Postretirement Plans | Spire Missouri
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Anticipated Contributions to pension plans for qualified trust	0
Employer contributions	$ 0

Information by Operating Segm_3

Information by Operating Segment - Additional Information (Details) - 3 months ended Dec. 31, 2018	reporting_unit	operating-segment
Segment Reporting [Abstract]
Number of reportable segments	2	2

Information by Operating Segm_4

Information by Operating Segment - Schedule of Operating Segment Information (Details) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Sep. 30, 2018
Operating Segment Information [Abstract]
Total Operating Revenues	$ 602	$ 561.8
Gas Utility
Natural and propane gas	251.7	240.8
Other operation and maintenance expenses	102.5	99
Depreciation and amortization	43.7	40.3
Taxes, other than income taxes	39.2	36.7
Total Gas Utility Operating Expenses	437.1	416.8
Gas Marketing and other	59.8	41
Total Operating Expenses	496.9	457.8
Operating Income	105.1	104
Net Economic Earnings (Loss)	65.9	57.9
Total Assets	7,232.2	6,701.1	$ 6,843.6
Eliminations
Operating Segment Information [Abstract]
Total Operating Revenues	(4.4)	(2.6)
Gas Utility
Natural and propane gas	(40.1)	(22.6)
Other operation and maintenance expenses	(2.4)	(1.9)
Depreciation and amortization	0	0
Taxes, other than income taxes	0	0
Total Gas Utility Operating Expenses	(42.5)	(24.5)
Gas Marketing and other	38.1	21.9
Total Operating Expenses	(4.4)	(2.6)
Operating Income	0	0
Net Economic Earnings (Loss)	0	0
Total Assets	(1,563.8)	(1,571.8)	(1,566.4)
Gas Utility
Operating Segment Information [Abstract]
Total Operating Revenues	573.8	541.9
Gas Utility | Eliminations
Operating Segment Information [Abstract]
Total Operating Revenues	1.4	0.1
Gas Utility | Operating Segments
Operating Segment Information [Abstract]
Total Operating Revenues	575.2	542
Gas Utility
Natural and propane gas	291.8	263.4
Other operation and maintenance expenses	104.9	100.9
Depreciation and amortization	43.7	40.3
Taxes, other than income taxes	39.2	36.7
Total Gas Utility Operating Expenses	479.6	441.3
Gas Marketing and other	0	0
Total Operating Expenses	479.6	441.3
Operating Income	95.6	100.7
Net Economic Earnings (Loss)	66.4	59.5
Total Assets	5,843.7	5,611.7	5,606.7
Gas Marketing
Operating Segment Information [Abstract]
Total Operating Revenues	25.8	19.6
Gas Marketing | Eliminations
Operating Segment Information [Abstract]
Total Operating Revenues	0	0
Gas Marketing | Operating Segments
Operating Segment Information [Abstract]
Total Operating Revenues	25.8	19.6
Gas Utility
Natural and propane gas	0	0
Other operation and maintenance expenses	0	0
Depreciation and amortization	0	0
Taxes, other than income taxes	0	0
Total Gas Utility Operating Expenses	0	0
Gas Marketing and other	13.3	14.6
Total Operating Expenses	13.3	14.6
Operating Income	12.5	5
Net Economic Earnings (Loss)	8.3	3.6
Total Assets	416.7	233.5	295.3
Corporate, Non-Segment
Operating Segment Information [Abstract]
Total Operating Revenues	2.4	0.3
Corporate, Non-Segment | Eliminations
Operating Segment Information [Abstract]
Total Operating Revenues	3	2.5
Corporate, Non-Segment | Operating Segments
Operating Segment Information [Abstract]
Total Operating Revenues	5.4	2.8
Gas Utility
Natural and propane gas	0	0
Other operation and maintenance expenses	0	0
Depreciation and amortization	0	0
Taxes, other than income taxes	0	0
Total Gas Utility Operating Expenses	0	0
Gas Marketing and other	8.4	4.5
Total Operating Expenses	8.4	4.5
Operating Income	(3)	(1.7)
Net Economic Earnings (Loss)	(8.8)	(5.2)
Total Assets	$ 2,535.6	$ 2,427.7	$ 2,508

Information by Operating Segm_5

Information by Operating Segment - Reconciliation of Consolidated Net Economic Earnings to Consolidated Net Income (Details) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Segment Reporting [Abstract]
Net Income (Loss)	$ 67.3	$ 116
Unrealized (gain) loss on energy-related derivatives	(2.2)	0.8
Realized gain on economic hedges prior to the sale of the physical commodity	0	(0.1)
Acquisition, divestiture and restructuring activities	0.4	1.7
Income tax effect of adjustments	0.4	(0.6)
Effect of the Tax Cuts and Jobs Act	0	(59.9)
Net Economic Earnings	$ 65.9	$ 57.9

Commitments and Contingencies -

Commitments and Contingencies - Additional Information - Commitments (Details) $ in Millions	3 Months Ended
	Dec. 31, 2018USD ($)
Long-term Purchase Commitment [Line Items]
Minimum total payments required for natural gas contracts	$ 1,691.8
Spire Missouri
Long-term Purchase Commitment [Line Items]
Minimum total payments required for natural gas contracts	731.8
Spire Alabama
Long-term Purchase Commitment [Line Items]
Minimum total payments required for natural gas contracts	$ 248.3

Commitments and Contingencies_2

Commitments and Contingencies - Additional Information - Contingencies (Details)	Dec. 17, 2013fatality	Dec. 31, 2018sitelawsuitplaintiff	Sep. 30, 2013site
Site Contingency [Line Items]
Number of lawsuits | lawsuit		14
Number of plaintiffs | plaintiff		1,600
Pending Litigation
Site Contingency [Line Items]
Number of lawsuits pending | plaintiff		13
Spire Missouri East
Site Contingency [Line Items]
Number of former manufactured gas plant (MGP) sites in Missouri		3
Number of sites enrolled in Brownfields/Voluntary clean up program		2
Spire Missouri East | Previous Ownership
Site Contingency [Line Items]
Number of former manufactured gas plant (MGP)			19
Spire Missouri West | Previous Ownership
Site Contingency [Line Items]
Number of former manufactured gas plant (MGP)		7
Spire Alabama
Site Contingency [Line Items]
Number of former manufactured gas plant (MGP)		9
Number of former manufactured gas distribution		5
Number of incident fatalities | fatality	1
Spire Alabama | Current Ownership
Site Contingency [Line Items]
Number of former manufactured gas plant (MGP)		4
Number of former manufactured gas distribution		1

Income Taxes - Additional Infor

Income Taxes - Additional Information (Details) $ in Millions	3 Months Ended
	Dec. 31, 2018USD ($)
Spire Missouri
Income Taxes [Line Items]
Excess accumulated deferred taxes returned	$ 2.1