Condensed Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	6 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Cash flows provided by (used in) operating activities:
Net income	$ 91,241us-gaap_NetIncomeLoss	$ 71,504us-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	(4,341)us-gaap_UnrealizedGainLossOnDerivatives	(1,353)us-gaap_UnrealizedGainLossOnDerivatives
Depreciation and amortization	13,178	10,087
Provision for losses on accounts receivable	3,567us-gaap_ProvisionForDoubtfulAccounts	4,478us-gaap_ProvisionForDoubtfulAccounts
Change in deferred taxes	7,776	8,190
Changes in operating assets and liabilities:
Increase in receivables	(145,609)us-gaap_IncreaseDecreaseInReceivables	(240,013)us-gaap_IncreaseDecreaseInReceivables
Decrease in inventories	8,581us-gaap_IncreaseDecreaseInInventories	13,146us-gaap_IncreaseDecreaseInInventories
Decrease in other assets	192	3,946
Increase in accounts payable	5,624	12,847
Decrease in customer credit balances	(42,309)	(52,425)
Increase in other current and long-term liabilities	65,700	47,893
Net cash provided by (used in) operating activities	3,600	(121,700)
Cash flows provided by (used in) investing activities:
Capital expenditures	(3,674)	(4,982)
Proceeds from sales of fixed assets	157	82
Acquisitions (net of cash acquired of $0, and $4,151, respectively)	(1,069)	(97,950)
Net cash used in investing activities	(4,586)	(102,850)
Cash flows provided by (used in) financing activities:
Revolving credit facility borrowings	12,296us-gaap_ProceedsFromLinesOfCredit	195,482us-gaap_ProceedsFromLinesOfCredit
Revolving credit facility repayments	(12,296)us-gaap_RepaymentsOfLinesOfCredit	(29,741)us-gaap_RepaymentsOfLinesOfCredit
Distributions	(10,195)us-gaap_PaymentsOfDividends	(9,622)us-gaap_PaymentsOfDividends
Unit repurchases	(691)us-gaap_PaymentsForRepurchaseOfEquity	(1,300)us-gaap_PaymentsForRepurchaseOfEquity
Deferred charges		(2,371)
Net cash provided by (used in) financing activities	(10,886)	152,448
Net decrease in cash and cash equivalents	(11,872)	(72,102)
Cash and cash equivalents at beginning of period	48,999	85,057
Cash and cash equivalents at end of period	$ 37,127	$ 12,955

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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.