Commitments and Contingencies	3 Months Ended
Dec. 31, 2012
Commitments and Contingencies [Abstract]
Commitments and Contingencies Disclosure [Text Block]	Legal and Regulatory Proceedings Certain conditions may exist as of the date that the financial statements are issued, which may result in a loss to the Company but which will only be resolved when one or more future events occur or fail to occur. The Company assesses such contingent liabilities, and such assessment inherently involves an exercise of judgment. In assessing loss contingencies related to legal and regulatory proceedings that are pending against the Company or unasserted claims that may result in such proceedings, the Company's legal counsel evaluates the perceived merits of any legal and regulatory proceedings or unasserted claims as well as the perceived merits of the amount of relief sought or expected to be sought therein. If the assessment of a contingency indicates that it is probable that a material loss had been incurred at the date of the financial statements and the amount of the liability can be estimated, then the estimated liability would be accrued in the Company's financial statements. If the assessment indicates that a potentially material loss contingency is not probable, but is reasonably possible, or is probable but cannot be estimated, then the nature of the contingent liability, together with an estimate of the range of possible loss if determinable and material, would be disclosed. Neither accrual nor disclosure is required for loss contingencies that are deemed remote. The Company accrues legal fees related to contingent liabilities as they are incurred. In addition to the matters discussed below, from time to time and in the ordinary course of business, the Company is involved in various legal and regulatory actions and proceedings, including tort claims, contractual disputes, employment matters, workers' compensation claims and collections. The Company carries insurance that provides protection against certain types of claims, up to the policy limits of the insurance. As of December 31, 2012 and September 30, 2012, the condensed consolidated balance sheets include loss contingency accruals recorded prior to September 30, 2012 and during the three months ended December 31, 2012, which are not material, individually or in the aggregate, to the Company's financial position or liquidity. During the three months ended December 31, 2012, the Company accrued expense related to loss contingencies of $1.5 million. In the opinion of management, possible exposure in these matters in excess of the amounts accrued, and in addition to the possible losses discussed below, is not material to the Company's earnings, financial position or liquidity. The following is a summary of significant legal matters involving the Company. Securities Litigation and Regulatory Proceedings FCStone and certain officers of FCStone were named as defendants in an action filed in the United States District Court for the Western District of Missouri in July 2008. A consolidated amended complaint ("CAC") was subsequently filed in September 2009. As alleged in the CAC, the action purports to be brought as a class action on behalf of purchasers of FCStone common stock between November 15, 2007 and February 24, 2009. The CAC seeks to hold defendants liable under Section 10(b) and Section 20(a) of the Securities Exchange Act of 1934 and concerns disclosures included in FCStone's fiscal year 2008 public filings. Specifically, the CAC relates to FCStone's public disclosures regarding an interest rate hedge, a bad debt expense arising from unprecedented events in the cotton trading market, and certain disclosures beginning on November 3, 2008 related to losses it expected to incur arising primarily from a customer energy trading account. FCStone and the named officers moved to dismiss the action. The parties to the litigation reached an agreement in principle to settle this matter during May 2012. The proposed settlement would be at no cost to the Company after consideration of insurance, and is subject to approval by the court. The terms of the settlement are expected to be presented to the court for approval before July 2013. In August 2008, a shareholder derivative action was filed against FCStone and certain directors of FCStone in the Circuit Court of Platte County, Missouri, alleging breaches of fiduciary duties, waste of corporate assets and unjust enrichment. An amended complaint was subsequently filed in May 2009 to add claims based upon the losses sustained by FCStone arising out of a customer energy trading account. In July 2009, the same plaintiff filed a motion for leave to amend the existing case to add a purported class action claim on behalf of the holders of FCStone common stock. In July 2009, a purported shareholder class action complaint was filed against FCStone and its directors, as well as the Company in the Circuit Court of Clay County, Missouri. The complaint alleged that FCStone and its directors breached their fiduciary duties by failing to maximize stockholder value in connection with the contemplated acquisition of FCStone by the Company. This complaint was subsequently consolidated with the complaint filed in the Circuit Court of Platte County, Missouri. The plaintiffs subsequently filed an amended consolidated complaint which does not assert any claims against the Company. This complaint purports to be filed derivatively on FCStone and the Company's behalf and against certain of FCStone's current and former directors and officers and directly against the same individuals. The Company, FCStone and the defendants filed motions to dismiss on multiple grounds. The parties to the litigation reached an agreement in principle to settle this matter during October 2012. The proposed settlement would result in the Company incurring a legal cost of $250,000 after consideration of insurance, and is subject to approval by the court. The terms of the settlement are expected to be presented to the court for approval before July 2013. As previously disclosed, the staff of the Fort Worth Regional Office of the SEC had conducted a formal investigation of FCStone's disclosures and accounting for losses associated with the customer energy trading account, which occurred prior to the Company's acquisition of FCStone on September 30, 2009. The Company cooperated fully with the SEC's staff in its investigation. During the quarter ended March 31, 2012, the Company was informed that the Staff of the SEC had closed its investigation of FCStone, and was not taking enforcement action against FCStone or any of its current or former officers. In November 2011, the Commodity Futures Trading Commission ("CFTC") Division of Enforcement Staff ("Staff") requested the Company to voluntarily produce specified documents to the Staff in connection with its then informal investigation of the losses that occurred in 2008 in the customer energy trading account of FCStone, LLC. In September 2012, the Staff provided the Company with a Wells notice, indicating the Staff's intention to recommend that the CFTC bring certain charges against FCStone, LLC. The Company filed its Wells Submission with the Staff in October 2012. The Company is in ongoing discussions with the CFTC regarding this matter. Sentinel Litigation The Company's subsidiary, FCStone, LLC, had a portion of its excess segregated funds invested with Sentinel Management Group Inc. ("Sentinel"), a registered FCM and an Illinois-based money manager that provided cash management services to other FCMs. In August 2007, Sentinel halted redemptions to customers and sold certain of the assets it managed to an unaffiliated third party at a significant discount. On August 17, 2007, subsequent to Sentinel's sale of certain assets, Sentinel filed for bankruptcy protection and $15.5 million of FCStone, LLC's $21.9 million in invested funds were returned to it. In August 2008, the bankruptcy trustee of Sentinel filed adversary proceedings against FCStone, LLC, and a number of other FCMs in the Bankruptcy Court for the Northern District of Illinois. The case was subsequently reassigned to the United States District Court, for the Northern District of Illinois. In the complaint, the trustee is seeking avoidance of alleged transfers or withdrawals of funds received by FCStone, LLC and other FCMs within 90 days prior to the filing of the Sentinel bankruptcy petition, as well as avoidance of post-petition distributions and disallowance of the proof of claim filed by FCStone, LLC. The trustee seeks recovery of pre- and post-petition transfers totaling approximately $15.5 million. In April 2009, the trustee filed an amended complaint adding a claim for unjust enrichment. FCStone, LLC answered the complaints and all parties entered into the discovery phase of the litigation. In January 2011, the trustee filed a motion for summary judgment on various counts in the adversary proceedings filed in August 2008 against FCStone, LLC and a number of other FCMs. In January 2012, FCStone, LLC filed a motion for summary judgment in its favor with respect to the transfer of approximately $1.1 million to its customer segregated account on August 17, 2007, pursuant to the "safe harbor" provisions of Section 546(e) of the U.S. Bankruptcy Code. In April 2012, FCStone, LLC filed a motion to dismiss a portion of the trustee's claims set forth in its amended complaint. The trial of this matter took place, as a test case, during October 2012. The trial court entered a judgment against FCStone, LLC on January 4, 2013. On January 17, 2013, the trial court entered an agreed order, staying execution and enforcement, pending an appeal of the judgment. By agreement, FCStone, LLC was required to post an appeal cash deposit of $8.0 million with the court, which was deposited on January 18, 2013. Based upon the merits of the Company's appeal, management believes a loss is not probable, and thus has not recorded a provision for this matter. The Company believes that if the appeal is unsuccessful, the resulting pre-tax loss to FCStone, LLC would be between $4 million and $6 million. Contractual Commitments Contingent Liabilities - Acquisitions Under the terms of the purchase agreements related to the acquisitions listed below, the Company has obligations to pay additional consideration if specific conditions and earnings targets are met. In accordance with the Business Combinations Topic of the ASC, the fair value of the additional consideration is recognized as a contingent liability as of the acquisition date. The contingent liability for these estimated additional purchase price considerations are included within ‘accounts payable and other accrued liabilities’ in the condensed consolidated balance sheets as of December 31, 2012 and September 30, 2012. The acquisition date fair value of additional consideration is remeasured to its fair value each reporting period, with changes in fair value recorded in current earnings. The Company has recorded an estimated contingent liability of $3.1 million, relating to the December 2012 acquisition of the institutional accounts of Tradewire Securities, LLC, as described in Note 16. The Company has a contingent liability relating to the November 2011 acquisition of Coffee Network, LLC, subsequently reorganized as a division of FCStone, LLC, which may result in the payment of additional purchase price consideration. The contingent liability recorded represents the fair value of the expected consideration to be paid, based on the forecasted adjusted pre-tax net earnings during the three annual periods following the closing of the acquisition plus a final contingent payment, and a discount rate being applied to those future payments. The present value of the estimated total purchase price, including contingent consideration, is less than $0.3 million as of December 31, 2012, of which less than $0.1 million has not been paid and is included within ‘accounts payable and other liabilities’ in the condensed consolidated balance sheet. The Company has a contingent liability relating to the October 2010 acquisition of Hencorp Becstone Futures, L.C., subsequently reorganized as a division of FCStone, LLC , which may result in the payment of additional purchase price consideration. The contingent liability recorded represents the fair value of the expected consideration to be paid, based on the forecasted adjusted pre-tax net earnings during the third and fourth fiscal years following the closing of the acquisition and a discount rate being applied to those future payments. The change in fair value for the three months ended December 31, 2012 was an increase of $0.1 million, included within ‘other expense’ in the condensed consolidated income statement. The present value of the estimated total purchase price, including contingent consideration, is $6.6 million as of December 31, 2012, of which $2.5 million has not been paid and is included within ‘accounts payable and other liabilities’ in the condensed consolidated balance sheet. The Company has a contingent liability relating to the July 2010 acquisition of the Hanley Companies, which may result in the payment of additional purchase price consideration. The contingent liability recorded represents contingent payments equal to 15% of the adjusted earnings before interest and taxes of the soft commodities derivatives business of the acquired Hanley Companies and INTL Hanley, LLC (the “Derivatives Division”) for the twelve-month period ending June 30, 2013 and a final contingent payment based on the cumulative adjusted earnings before taxes of the Derivatives Division for the three year period commencing on July 1, 2010, with a discount rate being applied to those future payments. Based on the purchase agreement, the remaining additional consideration is limited to a maximum of $10.0 million. The change in fair value for the three months ended December 31, 2012 was an increase of $0.2 million, included within ‘other expense’ in the condensed consolidated income statement. The present value of the estimated total purchase price, including contingent consideration, is $53.7 million as of December 31, 2012, of which $9.5 million has not been paid and is included within ‘accounts payable and other liabilities’ in the condensed consolidated balance sheet. The Company has a contingent liability relating to the April 2010 acquisition of the RMI Companies, subsequently reorganized as divisions of FCStone, LLC, which may result in the payment of additional consideration. The contingent liability recorded represents the fair value of expected consideration to be paid based on the forecasted sales during the twelve-month period ending March 31, 2013, and a discount rate being applied to that future payment. The change in fair value for the three months ended December 31, 2012 was an increase of $0.1 million, included within ‘other expense’ in the condensed consolidated income statement. The present value of the estimated total purchase price, including contingent consideration, is $15.2 million as of December 31, 2012, of which $3.0 million has not been paid and is included within ‘accounts payable and other liabilities’ in the condensed consolidated balance sheet. Exchange Member Guarantees The Company is a member of various exchanges that trade and clear futures and option contracts. Associated with its memberships, the Company may be required to pay a proportionate share of the financial obligations of another member who may default on its obligations to the exchanges. While the rules governing different exchange memberships vary, in general the Company’s guarantee obligations would arise only if the exchange had previously exhausted its resources. In addition, any such guarantee obligation would be apportioned among the other non-defaulting members of the exchange. Any potential contingent liability under these membership agreements cannot be estimated. The Company has not recorded any contingent liability in the condensed consolidated financial statements for these agreements and believes that any potential requirement to make payments under these agreements is remote.

Legal and Regulatory Proceedings

Certain conditions may exist as of the date that the financial statements are issued, which may result in a loss to the Company but which will only be resolved when one or more future events occur or fail to occur. The Company assesses such contingent liabilities, and such assessment inherently involves an exercise of judgment. In assessing loss contingencies related to legal and regulatory proceedings that are pending against the Company or unasserted claims that may result in such proceedings, the Company's legal counsel evaluates the perceived merits of any legal and regulatory proceedings or unasserted claims as well as the perceived merits of the amount of relief sought or expected to be sought therein.

If the assessment of a contingency indicates that it is probable that a material loss had been incurred at the date of the financial statements and the amount of the liability can be estimated, then the estimated liability would be accrued in the Company's financial statements. If the assessment indicates that a potentially material loss contingency is not probable, but is reasonably possible, or is probable but cannot be estimated, then the nature of the contingent liability, together with an estimate of the range of possible loss if determinable and material, would be disclosed. Neither accrual nor disclosure is required for loss contingencies that are deemed remote. The Company accrues legal fees related to contingent liabilities as they are incurred.

In addition to the matters discussed below, from time to time and in the ordinary course of business, the Company is involved in various legal and regulatory actions and proceedings, including tort claims, contractual disputes, employment matters, workers' compensation claims and collections. The Company carries insurance that provides protection against certain types of claims, up to the policy limits of the insurance.

As of December 31, 2012 and September 30, 2012, the condensed consolidated balance sheets include loss contingency accruals recorded prior to September 30, 2012 and during the three months ended December 31, 2012, which are not material, individually or in the aggregate, to the Company's financial position or liquidity. During the three months ended December 31, 2012, the Company accrued expense related to loss contingencies of $1.5 million. In the opinion of management, possible exposure in these matters in excess of the amounts accrued, and in addition to the possible losses discussed below, is not material to the Company's earnings, financial position or liquidity.

The following is a summary of significant legal matters involving the Company.

Securities Litigation and Regulatory Proceedings

FCStone and certain officers of FCStone were named as defendants in an action filed in the United States District Court for the Western District of Missouri in July 2008. A consolidated amended complaint ("CAC") was subsequently filed in September 2009. As alleged in the CAC, the action purports to be brought as a class action on behalf of purchasers of FCStone common stock between November 15, 2007 and February 24, 2009. The CAC seeks to hold defendants liable under Section 10(b) and Section 20(a) of the Securities Exchange Act of 1934 and concerns disclosures included in FCStone's fiscal year 2008 public filings. Specifically, the CAC relates to FCStone's public disclosures regarding an interest rate hedge, a bad debt expense arising from unprecedented events in the cotton trading market, and certain disclosures beginning on November 3, 2008 related to losses it expected to incur arising primarily from a customer energy trading account. FCStone and the named officers moved to dismiss the action. The parties to the litigation reached an agreement in principle to settle this matter during May 2012. The proposed settlement would be at no cost to the Company after consideration of insurance, and is subject to approval by the court. The terms of the settlement are expected to be presented to the court for approval before July 2013.

In August 2008, a shareholder derivative action was filed against FCStone and certain directors of FCStone in the Circuit Court of Platte County, Missouri, alleging breaches of fiduciary duties, waste of corporate assets and unjust enrichment. An amended complaint was subsequently filed in May 2009 to add claims based upon the losses sustained by FCStone arising out of a customer energy trading account. In July 2009, the same plaintiff filed a motion for leave to amend the existing case to add a purported class action claim on behalf of the holders of FCStone common stock.

In July 2009, a purported shareholder class action complaint was filed against FCStone and its directors, as well as the Company in the Circuit Court of Clay County, Missouri. The complaint alleged that FCStone and its directors breached their fiduciary duties by failing to maximize stockholder value in connection with the contemplated acquisition of FCStone by the Company. This complaint was subsequently consolidated with the complaint filed in the Circuit Court of Platte County, Missouri. The plaintiffs subsequently filed an amended consolidated complaint which does not assert any claims against the Company. This complaint purports to be filed derivatively on FCStone and the Company's behalf and against certain of FCStone's current and former directors and officers and directly against the same individuals. The Company, FCStone and the defendants filed motions to dismiss on multiple grounds. The parties to the litigation reached an agreement in principle to settle this matter during October 2012. The proposed settlement would result in the Company incurring a legal cost of $250,000 after consideration of insurance, and is subject to approval by the court. The terms of the settlement are expected to be presented to the court for approval before July 2013.

As previously disclosed, the staff of the Fort Worth Regional Office of the SEC had conducted a formal investigation of FCStone's disclosures and accounting for losses associated with the customer energy trading account, which occurred prior to the Company's acquisition of FCStone on September 30, 2009. The Company cooperated fully with the SEC's staff in its investigation. During the quarter ended March 31, 2012, the Company was informed that the Staff of the SEC had closed its investigation of FCStone, and was not taking enforcement action against FCStone or any of its current or former officers.

In November 2011, the Commodity Futures Trading Commission ("CFTC") Division of Enforcement Staff ("Staff") requested the Company to voluntarily produce specified documents to the Staff in connection with its then informal investigation of the losses that occurred in 2008 in the customer energy trading account of FCStone, LLC. In September 2012, the Staff provided the Company with a Wells notice, indicating the Staff's intention to recommend that the CFTC bring certain charges against FCStone, LLC. The Company filed its Wells Submission with the Staff in October 2012. The Company is in ongoing discussions with the CFTC regarding this matter.

Sentinel Litigation

The Company's subsidiary, FCStone, LLC, had a portion of its excess segregated funds invested with Sentinel Management Group Inc. ("Sentinel"), a registered FCM and an Illinois-based money manager that provided cash management services to other FCMs. In August 2007, Sentinel halted redemptions to customers and sold certain of the assets it managed to an unaffiliated third party at a significant discount. On August 17, 2007, subsequent to Sentinel's sale of certain assets, Sentinel filed for bankruptcy protection and $15.5 million of FCStone, LLC's $21.9 million in invested funds were returned to it.

In August 2008, the bankruptcy trustee of Sentinel filed adversary proceedings against FCStone, LLC, and a number of other FCMs in the Bankruptcy Court for the Northern District of Illinois. The case was subsequently reassigned to the United States District Court, for the Northern District of Illinois. In the complaint, the trustee is seeking avoidance of alleged transfers or withdrawals of funds received by FCStone, LLC and other FCMs within 90 days prior to the filing of the Sentinel bankruptcy petition, as well as avoidance of post-petition distributions and disallowance of the proof of claim filed by FCStone, LLC. The trustee seeks recovery of pre- and post-petition transfers totaling approximately $15.5 million. In April 2009, the trustee filed an amended complaint adding a claim for unjust enrichment. FCStone, LLC answered the complaints and all parties entered into the discovery phase of the litigation. In January 2011, the trustee filed a motion for summary judgment on various counts in the adversary proceedings filed in August 2008 against FCStone, LLC and a number of other FCMs. In January 2012, FCStone, LLC filed a motion for summary judgment in its favor with respect to the transfer of approximately $1.1 million to its customer segregated account on August 17, 2007, pursuant to the "safe harbor" provisions of Section 546(e) of the U.S. Bankruptcy Code. In April 2012, FCStone, LLC filed a motion to dismiss a portion of the trustee's claims set forth in its amended complaint. The trial of this matter took place, as a test case, during October 2012. The trial court entered a judgment against FCStone, LLC on January 4, 2013. On January 17, 2013, the trial court entered an agreed order, staying execution and enforcement, pending an appeal of the judgment. By agreement, FCStone, LLC was required to post an appeal cash deposit of $8.0 million with the court, which was deposited on January 18, 2013. Based upon the merits of the Company's appeal, management believes a loss is not probable, and thus has not recorded a provision for this matter. The Company believes that if the appeal is unsuccessful, the resulting pre-tax loss to FCStone, LLC would be between $4 million and $6 million.

Contractual Commitments

Contingent Liabilities - Acquisitions

Under the terms of the purchase agreements related to the acquisitions listed below, the Company has obligations to pay additional consideration if specific conditions and earnings targets are met. In accordance with the Business Combinations Topic of the ASC, the fair value of the additional consideration is recognized as a contingent liability as of the acquisition date. The contingent liability for these estimated additional purchase price considerations are included within ‘accounts payable and other accrued liabilities’ in the condensed consolidated balance sheets as of December 31, 2012 and September 30, 2012. The acquisition date fair value of additional consideration is remeasured to its fair value each reporting period, with changes in fair value recorded in current earnings.

The Company has recorded an estimated contingent liability of $3.1 million, relating to the December 2012 acquisition of the institutional accounts of Tradewire Securities, LLC, as described in Note 16.

The Company has a contingent liability relating to the November 2011 acquisition of Coffee Network, LLC, subsequently reorganized as a division of FCStone, LLC, which may result in the payment of additional purchase price consideration. The contingent liability recorded represents the fair value of the expected consideration to be paid, based on the forecasted adjusted pre-tax net earnings during the three annual periods following the closing of the acquisition plus a final contingent payment, and a discount rate being applied to those future payments. The present value of the estimated total purchase price, including contingent consideration, is less than $0.3 million as of December 31, 2012, of which less than $0.1 million has not been paid and is included within ‘accounts payable and other liabilities’ in the condensed consolidated balance sheet.

The Company has a contingent liability relating to the October 2010 acquisition of Hencorp Becstone Futures, L.C., subsequently reorganized as a division of FCStone, LLC , which may result in the payment of additional purchase price consideration. The contingent liability recorded represents the fair value of the expected consideration to be paid, based on the forecasted adjusted pre-tax net earnings during the third and fourth fiscal years following the closing of the acquisition and a discount rate being applied to those future payments. The change in fair value for the three months ended December 31, 2012 was an increase of $0.1 million, included within ‘other expense’ in the condensed consolidated income statement. The present value of the estimated total purchase price, including contingent consideration, is $6.6 million as of December 31, 2012, of which $2.5 million has not been paid and is included within ‘accounts payable and other liabilities’ in the condensed consolidated balance sheet.

The Company has a contingent liability relating to the July 2010 acquisition of the Hanley Companies, which may result in the payment of additional purchase price consideration. The contingent liability recorded represents contingent payments equal to 15% of the adjusted earnings before interest and taxes of the soft commodities derivatives business of the acquired Hanley Companies and INTL Hanley, LLC (the “Derivatives Division”) for the twelve-month period ending June 30, 2013 and a final contingent payment based on the cumulative adjusted earnings before taxes of the Derivatives Division for the three year period commencing on July 1, 2010, with a discount rate being applied to those future payments. Based on the purchase agreement, the remaining additional consideration is limited to a maximum of $10.0 million. The change in fair value for the three months ended December 31, 2012 was an increase of $0.2 million, included within ‘other expense’ in the condensed consolidated income statement. The present value of the estimated total purchase price, including contingent consideration, is $53.7 million as of December 31, 2012, of which $9.5 million has not been paid and is included within ‘accounts payable and other liabilities’ in the condensed consolidated balance sheet.

The Company has a contingent liability relating to the April 2010 acquisition of the RMI Companies, subsequently reorganized as divisions of FCStone, LLC, which may result in the payment of additional consideration. The contingent liability recorded represents the fair value of expected consideration to be paid based on the forecasted sales during the twelve-month period ending March 31, 2013, and a discount rate being applied to that future payment. The change in fair value for the three months ended December 31, 2012 was an increase of $0.1 million, included within ‘other expense’ in the condensed consolidated income statement. The present value of the estimated total purchase price, including contingent consideration, is $15.2 million as of December 31, 2012, of which $3.0 million has not been paid and is included within ‘accounts payable and other liabilities’ in the condensed consolidated balance sheet.

Exchange Member Guarantees

The Company is a member of various exchanges that trade and clear futures and option contracts. Associated with its memberships, the Company may be required to pay a proportionate share of the financial obligations of another member who may default on its obligations to the exchanges. While the rules governing different exchange memberships vary, in general the Company’s guarantee obligations would arise only if the exchange had previously exhausted its resources. In addition, any such guarantee obligation would be apportioned among the other non-defaulting members of the exchange. Any potential contingent liability under these membership agreements cannot be estimated. The Company has not recorded any contingent liability in the condensed consolidated financial statements for these agreements and believes that any potential requirement to make payments under these agreements is remote.