Condensed Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	3 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Cash flows provided by (used in) operating activities:
Net income	$ 15,554us-gaap_NetIncomeLoss	$ 19,288us-gaap_NetIncomeLoss
Adjustment to reconcile net income to net cash provided by (used in) operating activities:
(Increase) decrease in the fair value of derivative instruments	8,290us-gaap_UnrealizedGainLossOnDerivatives	(5,458)us-gaap_UnrealizedGainLossOnDerivatives
Depreciation and amortization	6,558	4,779
Provision for losses on accounts receivable	236us-gaap_ProvisionForDoubtfulAccounts	796us-gaap_ProvisionForDoubtfulAccounts
Change in deferred taxes	230	3,332
Changes in operating assets and liabilities:
Increase in receivables	(58,241)us-gaap_IncreaseDecreaseInReceivables	(107,604)us-gaap_IncreaseDecreaseInReceivables
Increase in inventories	(8,633)us-gaap_IncreaseDecreaseInInventories	(16,140)us-gaap_IncreaseDecreaseInInventories
Increase in other assets	(5,565)	(1,977)
Increase in accounts payable	20,261	21,253
Decrease in customer credit balances	(5,862)	(20,119)
Increase in other current and long-term liabilities	13,752	8,711
Net cash used in operating activities	(13,420)	(93,139)
Cash flows provided by (used in) investing activities:
Capital expenditures	(1,772)	(2,992)
Proceeds from sales of fixed assets	88	71
Net cash used in investing activities	(1,684)	(2,921)
Cash flows provided by (used in) financing activities:
Revolving credit facility borrowings		100,348us-gaap_ProceedsFromLinesOfCredit
Distributions	(5,098)us-gaap_PaymentsOfDividends	(4,811)us-gaap_PaymentsOfDividends
Unit repurchases	(691)us-gaap_PaymentsForRepurchaseOfEquity	(1,300)us-gaap_PaymentsForRepurchaseOfEquity
Net cash provided by (used in) financing activities	(5,789)	94,237
Net decrease in cash and cash equivalents	(20,893)	(1,823)
Cash and cash equivalents at beginning of period	48,999	85,057
Cash and cash equivalents at end of period	$ 28,106	$ 83,234

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.