Subsequent Events Subsequent Events (Narrative) (Details) (Subsequent Event [Member], USD $) In Millions, except Share data in Thousands, unless otherwise specified	0 Months Ended	1 Months Ended
Jun. 08, 2015	Jul. 31, 2015
Common Unit, Issued	6,325
Cash [Member]
Business Combination, Consideration Transferred		$ 562.5
Common Stock [Member]
Business Combination, Consideration Transferred		11.2
Fixed Rate Six Point Seven Five Due Two Thousand Twenty Three [Member]
Debt Instrument, Interest Rate, Stated Percentage	6.75%
Proceeds from Debt, Net of Issuance Costs	491.3
Debt Instrument, Maturity Date	Jun. 01, 2023
Debt principal amount	500.0
Ferrellgas, L.P. [Member]
Common Unit, Issued	6,325
Ferrellgas, L.P. [Member] \| Cash [Member]
Business Combination, Consideration Transferred		562.5
Ferrellgas, L.P. [Member] \| Common Stock [Member]
Business Combination, Consideration Transferred		11.2
Ferrellgas, L.P. [Member] \| Fixed Rate Six Point Seven Five Due Two Thousand Twenty Three [Member]
Debt Instrument, Interest Rate, Stated Percentage	6.75%
Proceeds from Debt, Net of Issuance Costs	491.3
Debt Instrument, Maturity Date	Jun. 01, 2023
Debt principal amount	500.0
Ferrellgas Finance Corp. [Member] \| Fixed Rate Six Point Seven Five Due Two Thousand Twenty Three [Member]
Debt Instrument, Interest Rate, Stated Percentage	6.75%
Debt Instrument, Maturity Date	Jun. 01, 2023
Debt principal amount	500.0

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Face (par) amount of debt instrument at time of issuance.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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The cash inflow from additional borrowings, net of cash paid to third parties in connection with debt origination.

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Number of new stock issued during the period.

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