FAIR VALUE MEASUREMENTS (Details) - Fair Value, Measurements, Recurring - USD ($) $ in Millions | Dec. 31, 2016 | Sep. 30, 2016 | Dec. 31, 2015 |
LIABILITIES | | | |
Effects of Netting and Cash Margin Receivables /Payables | $ (10.4) | | |
Derivative liability | 3.5 | | |
Laclede Gas | | | |
ASSETS | | | |
Effects of Netting and Cash Margin Receivables /Payables | (6.6) | $ (0.7) | $ (0.1) |
Derivative asset | 23.9 | 25.8 | 19.9 |
LIABILITIES | | | |
Effects of Netting and Cash Margin Receivables /Payables | (0.2) | (1.6) | (17.4) |
Derivative liability | 0 | 0.2 | 4.6 |
Quoted Prices in Active Markets (Level 1) | | | |
LIABILITIES | | | |
Derivative liability before netting adjustment | 5.3 | | |
Quoted Prices in Active Markets (Level 1) | Laclede Gas | | | |
ASSETS | | | |
Derivative asset before netting adjustment | 26.5 | 22.4 | 16 |
LIABILITIES | | | |
Derivative liability before netting adjustment | 0.2 | 1.6 | 17.4 |
Significant Observable Inputs (Level 2) | | | |
LIABILITIES | | | |
Derivative liability before netting adjustment | 8.6 | | |
Significant Observable Inputs (Level 2) | Laclede Gas | | | |
ASSETS | | | |
Derivative asset before netting adjustment | 4 | 4.1 | 4 |
LIABILITIES | | | |
Derivative liability before netting adjustment | 0 | 0.2 | 4.6 |
Significant Unobservable Inputs (Level 3) | | | |
LIABILITIES | | | |
Derivative liability before netting adjustment | 0 | | |
Significant Unobservable Inputs (Level 3) | Laclede Gas | | | |
ASSETS | | | |
Derivative asset before netting adjustment | 0 | 0 | 0 |
LIABILITIES | | | |
Derivative liability before netting adjustment | 0 | 0 | 0 |
US stock/bond mutual funds | Laclede Gas | | | |
ASSETS | | | |
Effects of Netting and Cash Margin Receivables /Payables | 0 | 0 | 0 |
Derivative asset | 21.2 | 20.9 | 19.9 |
US stock/bond mutual funds | Quoted Prices in Active Markets (Level 1) | Laclede Gas | | | |
ASSETS | | | |
Derivative asset before netting adjustment | 17.2 | 16.8 | 15.9 |
US stock/bond mutual funds | Significant Observable Inputs (Level 2) | Laclede Gas | | | |
ASSETS | | | |
Derivative asset before netting adjustment | 4 | 4.1 | 4 |
US stock/bond mutual funds | Significant Unobservable Inputs (Level 3) | Laclede Gas | | | |
ASSETS | | | |
Derivative asset before netting adjustment | 0 | 0 | 0 |
NYMEX/ICE natural gas contracts | Laclede Gas | | | |
ASSETS | | | |
Effects of Netting and Cash Margin Receivables /Payables | (6.6) | (0.4) | (0.1) |
Derivative asset | 2.2 | 4.9 | 0 |
LIABILITIES | | | |
Effects of Netting and Cash Margin Receivables /Payables | (0.2) | (1.6) | (17.3) |
Derivative liability | 0 | 0 | 0 |
NYMEX/ICE natural gas contracts | Quoted Prices in Active Markets (Level 1) | Laclede Gas | | | |
ASSETS | | | |
Derivative asset before netting adjustment | 8.8 | 5.3 | 0.1 |
LIABILITIES | | | |
Derivative liability before netting adjustment | 0.2 | 1.6 | 17.3 |
NYMEX/ICE natural gas contracts | Significant Observable Inputs (Level 2) | Laclede Gas | | | |
ASSETS | | | |
Derivative asset before netting adjustment | 0 | 0 | 0 |
LIABILITIES | | | |
Derivative liability before netting adjustment | 0 | 0 | 0 |
NYMEX/ICE natural gas contracts | Significant Unobservable Inputs (Level 3) | Laclede Gas | | | |
ASSETS | | | |
Derivative asset before netting adjustment | 0 | 0 | 0 |
LIABILITIES | | | |
Derivative liability before netting adjustment | 0 | 0 | 0 |
OTCBB natural gas contracts | Laclede Gas | | | |
LIABILITIES | | | |
Effects of Netting and Cash Margin Receivables /Payables | | 0 | 0 |
Derivative liability | | 0.2 | 4.6 |
OTCBB natural gas contracts | Quoted Prices in Active Markets (Level 1) | Laclede Gas | | | |
LIABILITIES | | | |
Derivative liability before netting adjustment | | 0 | 0 |
OTCBB natural gas contracts | Significant Observable Inputs (Level 2) | Laclede Gas | | | |
LIABILITIES | | | |
Derivative liability before netting adjustment | | 0.2 | 4.6 |
OTCBB natural gas contracts | Significant Unobservable Inputs (Level 3) | Laclede Gas | | | |
LIABILITIES | | | |
Derivative liability before netting adjustment | | 0 | 0 |
Gasoline and heating oil contracts | Laclede Gas | | | |
ASSETS | | | |
Effects of Netting and Cash Margin Receivables /Payables | 0 | (0.3) | |
Derivative asset | 0.5 | 0 | |
LIABILITIES | | | |
Effects of Netting and Cash Margin Receivables /Payables | | | (0.1) |
Derivative liability | | | 0 |
Gasoline and heating oil contracts | Quoted Prices in Active Markets (Level 1) | Laclede Gas | | | |
ASSETS | | | |
Derivative asset before netting adjustment | 0.5 | 0.3 | |
LIABILITIES | | | |
Derivative liability before netting adjustment | | | 0.1 |
Gasoline and heating oil contracts | Significant Observable Inputs (Level 2) | Laclede Gas | | | |
ASSETS | | | |
Derivative asset before netting adjustment | 0 | 0 | |
LIABILITIES | | | |
Derivative liability before netting adjustment | | | 0 |
Gasoline and heating oil contracts | Significant Unobservable Inputs (Level 3) | Laclede Gas | | | |
ASSETS | | | |
Derivative asset before netting adjustment | 0 | 0 | |
LIABILITIES | | | |
Derivative liability before netting adjustment | | | 0 |
Other | Interest rate swaps | | | |
LIABILITIES | | | |
Effects of Netting and Cash Margin Receivables /Payables | 0 | 0 | |
Derivative liability | 8.2 | 3 | |
Other | Interest rate swaps | Quoted Prices in Active Markets (Level 1) | | | |
LIABILITIES | | | |
Derivative liability before netting adjustment | 0 | 0 | |
Other | Interest rate swaps | Significant Observable Inputs (Level 2) | | | |
LIABILITIES | | | |
Derivative liability before netting adjustment | 8.2 | 3 | |
Other | Interest rate swaps | Significant Unobservable Inputs (Level 3) | | | |
LIABILITIES | | | |
Derivative liability before netting adjustment | 0 | 0 | |
Gas Utility | | | |
ASSETS | | | |
Effects of Netting and Cash Margin Receivables /Payables | (6.6) | (0.7) | (0.1) |
Derivative asset | 24.1 | 25.9 | 19.9 |
LIABILITIES | | | |
Effects of Netting and Cash Margin Receivables /Payables | (0.2) | (1.6) | (17.4) |
Derivative liability | 0 | 0.2 | 4.6 |
Gas Utility | Quoted Prices in Active Markets (Level 1) | | | |
ASSETS | | | |
Derivative asset before netting adjustment | 26.7 | 22.5 | 16 |
LIABILITIES | | | |
Derivative liability before netting adjustment | 0.2 | 1.6 | 17.4 |
Gas Utility | Significant Observable Inputs (Level 2) | | | |
ASSETS | | | |
Derivative asset before netting adjustment | 4 | 4.1 | 4 |
LIABILITIES | | | |
Derivative liability before netting adjustment | 0 | 0.2 | 4.6 |
Gas Utility | Significant Unobservable Inputs (Level 3) | | | |
ASSETS | | | |
Derivative asset before netting adjustment | 0 | 0 | 0 |
LIABILITIES | | | |
Derivative liability before netting adjustment | 0 | 0 | 0 |
Gas Utility | US stock/bond mutual funds | | | |
ASSETS | | | |
Effects of Netting and Cash Margin Receivables /Payables | 0 | 0 | 0 |
Derivative asset | 21.2 | 20.9 | 19.9 |
Gas Utility | US stock/bond mutual funds | Quoted Prices in Active Markets (Level 1) | | | |
ASSETS | | | |
Derivative asset before netting adjustment | 17.2 | 16.8 | 15.9 |
Gas Utility | US stock/bond mutual funds | Significant Observable Inputs (Level 2) | | | |
ASSETS | | | |
Derivative asset before netting adjustment | 4 | 4.1 | 4 |
Gas Utility | US stock/bond mutual funds | Significant Unobservable Inputs (Level 3) | | | |
ASSETS | | | |
Derivative asset before netting adjustment | 0 | 0 | 0 |
Gas Utility | NYMEX/ICE natural gas contracts | | | |
ASSETS | | | |
Effects of Netting and Cash Margin Receivables /Payables | (6.6) | (0.4) | (0.1) |
Derivative asset | 2.2 | 4.9 | 0 |
LIABILITIES | | | |
Effects of Netting and Cash Margin Receivables /Payables | (0.2) | (1.6) | (17.3) |
Derivative liability | 0 | 0 | 0 |
Gas Utility | NYMEX/ICE natural gas contracts | Quoted Prices in Active Markets (Level 1) | | | |
ASSETS | | | |
Derivative asset before netting adjustment | 8.8 | 5.3 | 0.1 |
LIABILITIES | | | |
Derivative liability before netting adjustment | 0.2 | 1.6 | 17.3 |
Gas Utility | NYMEX/ICE natural gas contracts | Significant Observable Inputs (Level 2) | | | |
ASSETS | | | |
Derivative asset before netting adjustment | 0 | 0 | 0 |
LIABILITIES | | | |
Derivative liability before netting adjustment | 0 | 0 | 0 |
Gas Utility | NYMEX/ICE natural gas contracts | Significant Unobservable Inputs (Level 3) | | | |
ASSETS | | | |
Derivative asset before netting adjustment | 0 | 0 | 0 |
LIABILITIES | | | |
Derivative liability before netting adjustment | 0 | 0 | 0 |
Gas Utility | OTCBB natural gas contracts | | | |
LIABILITIES | | | |
Effects of Netting and Cash Margin Receivables /Payables | | 0 | 0 |
Derivative liability | | 0.2 | 4.6 |
Gas Utility | OTCBB natural gas contracts | Quoted Prices in Active Markets (Level 1) | | | |
LIABILITIES | | | |
Derivative liability before netting adjustment | | 0 | 0 |
Gas Utility | OTCBB natural gas contracts | Significant Observable Inputs (Level 2) | | | |
LIABILITIES | | | |
Derivative liability before netting adjustment | | 0.2 | 4.6 |
Gas Utility | OTCBB natural gas contracts | Significant Unobservable Inputs (Level 3) | | | |
LIABILITIES | | | |
Derivative liability before netting adjustment | | 0 | 0 |
Gas Utility | NYMEX gasoline and heating oil contracts | | | |
LIABILITIES | | | |
Effects of Netting and Cash Margin Receivables /Payables | | | (0.1) |
Derivative liability | | | 0 |
Gas Utility | NYMEX gasoline and heating oil contracts | Quoted Prices in Active Markets (Level 1) | | | |
LIABILITIES | | | |
Derivative liability before netting adjustment | | | 0.1 |
Gas Utility | NYMEX gasoline and heating oil contracts | Significant Observable Inputs (Level 2) | | | |
LIABILITIES | | | |
Derivative liability before netting adjustment | | | 0 |
Gas Utility | NYMEX gasoline and heating oil contracts | Significant Unobservable Inputs (Level 3) | | | |
LIABILITIES | | | |
Derivative liability before netting adjustment | | | 0 |
Gas Utility | Gasoline and heating oil contracts | | | |
ASSETS | | | |
Effects of Netting and Cash Margin Receivables /Payables | 0 | (0.3) | |
Derivative asset | 0.7 | 0.1 | |
Gas Utility | Gasoline and heating oil contracts | Quoted Prices in Active Markets (Level 1) | | | |
ASSETS | | | |
Derivative asset before netting adjustment | 0.7 | 0.4 | |
Gas Utility | Gasoline and heating oil contracts | Significant Observable Inputs (Level 2) | | | |
ASSETS | | | |
Derivative asset before netting adjustment | 0 | 0 | |
Gas Utility | Gasoline and heating oil contracts | Significant Unobservable Inputs (Level 3) | | | |
ASSETS | | | |
Derivative asset before netting adjustment | 0 | 0 | |
Gas Marketing | | | |
ASSETS | | | |
Effects of Netting and Cash Margin Receivables /Payables | | (5) | |
Derivative asset | | 34.3 | |
LIABILITIES | | | |
Effects of Netting and Cash Margin Receivables /Payables | | (7.6) | (22.7) |
Derivative liability | | 4.9 | 5.7 |
Gas Marketing | Quoted Prices in Active Markets (Level 1) | | | |
ASSETS | | | |
Derivative asset before netting adjustment | | 22.9 | |
LIABILITIES | | | |
Derivative liability before netting adjustment | | 5.1 | 18.9 |
Gas Marketing | Significant Observable Inputs (Level 2) | | | |
ASSETS | | | |
Derivative asset before netting adjustment | | 16.2 | |
LIABILITIES | | | |
Derivative liability before netting adjustment | | 7.4 | 9.5 |
Gas Marketing | Significant Unobservable Inputs (Level 3) | | | |
ASSETS | | | |
Derivative asset before netting adjustment | | 0.2 | |
LIABILITIES | | | |
Derivative liability before netting adjustment | | 0 | 0 |
Gas Marketing | US stock/bond mutual funds | | | |
ASSETS | | | |
Effects of Netting and Cash Margin Receivables /Payables | (11.8) | | (7.3) |
Derivative asset | 42.1 | | 24.7 |
Gas Marketing | US stock/bond mutual funds | Quoted Prices in Active Markets (Level 1) | | | |
ASSETS | | | |
Derivative asset before netting adjustment | 27.4 | | 20.1 |
Gas Marketing | US stock/bond mutual funds | Significant Observable Inputs (Level 2) | | | |
ASSETS | | | |
Derivative asset before netting adjustment | 26.5 | | 11.7 |
Gas Marketing | US stock/bond mutual funds | Significant Unobservable Inputs (Level 3) | | | |
ASSETS | | | |
Derivative asset before netting adjustment | 0 | | 0.2 |
Gas Marketing | NYMEX/ICE natural gas contracts | | | |
ASSETS | | | |
Effects of Netting and Cash Margin Receivables /Payables | (4.9) | (3.4) | (6.9) |
Derivative asset | 0.3 | 0.4 | 3 |
LIABILITIES | | | |
Effects of Netting and Cash Margin Receivables /Payables | (9.9) | (5.1) | (5) |
Derivative liability | 0 | 0 | 0 |
Gas Marketing | NYMEX/ICE natural gas contracts | Quoted Prices in Active Markets (Level 1) | | | |
ASSETS | | | |
Derivative asset before netting adjustment | 0.7 | 0.4 | 4.1 |
LIABILITIES | | | |
Derivative liability before netting adjustment | 5.1 | 3.5 | 1.5 |
Gas Marketing | NYMEX/ICE natural gas contracts | Significant Observable Inputs (Level 2) | | | |
ASSETS | | | |
Derivative asset before netting adjustment | 4.5 | 3.4 | 5.8 |
LIABILITIES | | | |
Derivative liability before netting adjustment | 4.8 | 1.6 | 3.5 |
Gas Marketing | NYMEX/ICE natural gas contracts | Significant Unobservable Inputs (Level 3) | | | |
ASSETS | | | |
Derivative asset before netting adjustment | 0 | 0 | 0 |
LIABILITIES | | | |
Derivative liability before netting adjustment | 0 | 0 | 0 |
Gas Marketing | Natural gas commodity contracts | | | |
ASSETS | | | |
Effects of Netting and Cash Margin Receivables /Payables | (0.3) | (0.9) | (0.3) |
Derivative asset | 9.5 | 8 | 1.8 |
LIABILITIES | | | |
Effects of Netting and Cash Margin Receivables /Payables | (0.3) | (0.9) | (0.3) |
Derivative liability | 3.5 | 1.7 | 1.1 |
Gas Marketing | Natural gas commodity contracts | Quoted Prices in Active Markets (Level 1) | | | |
ASSETS | | | |
Derivative asset before netting adjustment | 0 | 0 | 0 |
LIABILITIES | | | |
Derivative liability before netting adjustment | 0 | 0 | 0 |
Gas Marketing | Natural gas commodity contracts | Significant Observable Inputs (Level 2) | | | |
ASSETS | | | |
Derivative asset before netting adjustment | 9.8 | 8.7 | 1.9 |
LIABILITIES | | | |
Derivative liability before netting adjustment | 3.8 | 2.6 | 1.4 |
Gas Marketing | Natural gas commodity contracts | Significant Unobservable Inputs (Level 3) | | | |
ASSETS | | | |
Derivative asset before netting adjustment | 0 | 0.2 | 0.2 |
LIABILITIES | | | |
Derivative liability before netting adjustment | $ 0 | $ 0 | $ 0 |