Assets and Liabilities, at Fair Value (Tables)

6 Months Ended

Mar. 31, 2016

Assets and Liabilities, at Fair Value [Abstract]

Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block]

The following tables set forth the Company’s financial and nonfinancial assets and liabilities accounted for at fair value, on a recurring basis, as of March 31, 2016 by level in the fair value hierarchy. There were no assets or liabilities that were measured at fair value on a nonrecurring basis as of March 31, 2016.

	March 31, 2016
(in millions)	Level 1		Level 2		Level 3		Netting and Collateral (1)			Total
Assets:
Unrestricted cash equivalents - certificate of deposits	$	1.2	$	—	$	—	$	—		$	1.2
Commodities warehouse receipts	18.1		—		—		—			18.1
U.S. government obligations	—		552.8		—		—			552.8
Securities and other assets segregated under federal and other regulations	18.1		552.8		—		—			570.9
Money market funds	652.7		—		—		—			652.7
U.S. government obligations	—		215.2		—		—			215.2
Derivatives	2,001.7		—		—		(1,973.9		)	27.8
Deposits with and receivables from exchange-clearing organizations	2,654.4		215.2		—		(1,973.9		)	895.7
"To be announced" (TBA) and forward settling securities	—		2.9		—		(2.1		)	0.8
Derivatives	—		201.1		—		(217.9		)	(16.8		)
Deposits with and receivables from broker-dealers, clearing organizations and counterparties	—		204.0		—		(220.0		)	(16.0		)
Common and preferred stock and American Depositary Receipts (“ADRs”)	55.4		1.8		0.3		—			57.5
Exchangeable foreign ordinary equities and ADRs	140.6		1.9		—		—			142.5
Corporate and municipal bonds	32.5		1.9		3.3		—			37.7
U.S. government obligations	—		643.7		—		—			643.7
Foreign government obligations	—		10.5		—		—			10.5
Mortgage-backed securities	—		698.8		—		—			698.8
Derivatives	213.2		1,488.2		—		(1,475.2		)	226.2
Commodities leases	—		145.8		—		(117.3		)	28.5
Commodities warehouse receipts	6.5		—		—		—			6.5
Exchange firm common stock	5.8		—		—		—			5.8
Mutual funds and other	7.2		—		—		—			7.2
Financial instruments owned	461.2		2,992.6		3.6		(1,592.5		)	1,864.9
Physical commodities inventory, net - precious metals	2.8		—		—		—			2.8
Total assets at fair value	$	3,137.7	$	3,964.6	$	3.6	$	(3,786.4	)	$	3,319.5
Liabilities:
Accounts payable and other accrued liabilities - contingent liabilities	$	—	$	—	$	1.5	$	—		$	1.5
TBA and forward settling securities	—		4.1		—		(2.1		)	2.0
Derivatives	2,001.9		261.9		—		(2,263.9		)	(0.1		)
Payable to broker-dealers, clearing organizations and counterparties	2,001.9		266.0		—		(2,266.0		)	1.9
Common and preferred stock and ADRs	33.4		1.3		—		—			34.7
Exchangeable foreign ordinary equities and ADRs	138.7		4.1		—		—			142.8
Corporate and municipal bonds	8.6		—		—		—			8.6
U.S. government obligations	—		608.4		—		—			608.4
Mortgage-backed securities	—		0.8		—		—			0.8
Derivatives	216.5		1,410.9		—		(1,447.6		)	179.8
Commodities leases	—		167.2		—		(108.4		)	58.8
Financial instruments sold, not yet purchased	397.2		2,192.7		—		(1,556.0		)	1,033.9
Total liabilities at fair value	$	2,399.1	$	2,458.7	$	1.5	$	(3,822.0	)	$	1,037.3

(1) Represents cash collateral and the impact of netting across the levels of the fair value hierarchy. Netting among positions classified within the same level is included in that level.

The following table sets forth the Company’s financial and nonfinancial assets and liabilities accounted for at fair value, on a recurring basis, as of September 30, 2015 by level in the fair value hierarchy.

	September 30, 2015
(in millions)	Level 1		Level 2		Level 3		Netting and Collateral (1)			Total
Assets:
Unrestricted cash equivalents - certificates of deposits	$	1.3	$	—	$	—	$	—		$	1.3
Commodities warehouse receipts	22.1		—		—		—			22.1
U.S. government obligations	—		493.4		—		—			493.4
Securities and other assets segregated under federal and other regulations	22.1		493.4		—		—			515.5
Money market funds	431.8		—		—		—			431.8
U.S. government obligations	—		501.4		—		—			501.4
Derivatives	3,615.9		—		—		(3,539.7		)	76.2
Deposits with and receivables from exchange-clearing organizations	4,047.7		501.4		—		(3,539.7		)	1,009.4
TBA and forward settling securities	—		1.2		—		(1.0		)	0.2
Derivatives	0.1		537.9		—		(591.1		)	(53.1		)
Deposits with and receivables from broker-dealers, clearing organizations and counterparties	0.1		539.1		—		(592.1		)	(52.9		)
Common and preferred stock and ADRs	23.7		1.9		0.5		—			26.1
Exchangeable foreign ordinary equities and ADRs	82.9		6.6		—		—			89.5
Corporate and municipal bonds	26.1		2.0		3.2		—			31.3
U.S. government obligations	—		513.4		—		—			513.4
Foreign government obligations	—		12.1		—		—			12.1
Mortgage-backed securities	—		699.5		—		—			699.5
Derivatives	278.5		1,702.0		—		(1,949.9		)	30.6
Commodities leases	—		64.6		—		(57.0		)	7.6
Commodities warehouse receipts	2.8		—		—		—			2.8
Exchange firm common stock	5.6		—		—		—			5.6
Mutual funds and other	3.4		—		—		—			3.4
Financial instruments owned	423.0		3,002.1		3.7		(2,006.9		)	1,421.9
Physical commodities inventory, net - precious metals	15.2		—		—		—			15.2
Total assets at fair value	$	4,509.4	$	4,536.0	$	3.7	$	(6,138.7	)	$	2,910.4
Liabilities:
Accounts payable and other accrued liabilities - contingent liabilities	$	—	$	—	$	3.3	$	—		$	3.3
TBA and forward settling securities	—		2.6		—		(1.0		)	1.6
Derivatives	3,491.3		528.7		—		(4,020.0		)	—
Payable to broker-dealers, clearing organizations and counterparties	3,491.3		531.3		—		(4,021.0		)	1.6
Common and preferred stock and ADRs	18.0		0.6		—		—			18.6
Exchangeable foreign ordinary equities and ADRs	89.0		1.0		—		—			90.0
U.S. government obligations	—		341.0		—		—			341.0
Foreign government obligations	—		6.4		—		—			6.4
Mortgage-backed securities	—		2.8		—		—			2.8
Derivatives	264.0		1,723.5		—		(1,933.4		)	54.1
Commodities leases	—		99.1		—		(43.7		)	55.4
Financial instruments sold, not yet purchased	371.0		2,174.4		—		(1,977.1		)	568.3
Total liabilities at fair value	$	3,862.3	$	2,705.7	$	3.3	$	(5,998.1	)	$	573.2

(1) Represents cash collateral and the impact of netting across the levels of the fair value hierarchy. Netting among positions classified within the same level is included in that level.

Fair Value, Assets and Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block]

Information on Level 3 Financial Assets and Liabilities

The Company’s financial assets at fair value classified in level 3 of the fair value hierarchy as of March 31, 2016 and September 30, 2015 are summarized below:

(in millions)	March 31, 2016			September 30, 2015
Total level 3 assets	$	3.6		$	3.7
Level 3 assets for which the Company bears economic exposure	$	3.6		$	3.7
Total assets	$	5,657.9		$	5,070.0
Total assets at fair value	$	3,319.5		$	2,910.4
Total level 3 assets as a percentage of total assets	0.1		%	0.1		%
Level 3 assets for which the Company bears economic exposure as a percentage of total assets	0.1		%	0.1		%
Total level 3 assets as a percentage of total financial assets at fair value	0.1		%	0.1		%

The following tables set forth a summary of changes in the fair value of the Company’s level 3 financial assets and liabilities during the three and six months ended March 31, 2016 and 2015, including a summary of unrealized gains (losses) during the respective periods on the Company’s level 3 financial assets and liabilities still held as of March 31, 2016.

	Level 3 Financial Assets and Financial Liabilities For the Three Months Ended March 31, 2016
(in millions)	Balances at beginning of period		Realized gains (losses) during period		Unrealized gains (losses) during period		Purchases/issuances		Settlements			Transfers in or (out) of Level 3		Balances at end of period
Assets:
Common stock and ADRs	$	0.3	$	—	$	—	$	—	$	—		$	—	$	0.3
Corporate and municipal bonds	3.2		—		0.1		—		—			—		3.3
	$	3.5	$	—	$	0.1	$	—	$	—		$	—	$	3.6
Liabilities:
Contingent liabilities	$	3.5	$	—	$	0.1	$	—	$	(2.1	)	$	—	$	1.5

	Level 3 Financial Assets and Financial Liabilities For the Six Months Ended March 31, 2016
(in millions)	Balances at beginning of period		Realized gains (losses) during period		Unrealized gains (losses) during period			Purchases/issuances		Settlements			Transfers in or (out) of Level 3		Balances at end of period
Assets:
Common stock and ADRs	$	0.5	$	—	$	(0.2	)	$	—	$	—		$	—	$	0.3
Corporate and municipal bonds	3.2		—		0.1			—		—			—		3.3
	$	3.7	$	—	$	(0.1	)	$	—	$	—		$	—	$	3.6
Liabilities:
Contingent liabilities	$	3.3	$	—	$	0.3		$	—	$	(2.1	)	$	—	$	1.5

	Level 3 Financial Assets and Financial Liabilities For the Three Months Ended March 31, 2015
(in millions)	Balances at beginning of period		Realized gains (losses) during period		Unrealized gains (losses) during period			Purchases/issuances		Settlements			Transfers in or (out) of Level 3		Balances at end of period
Assets:
Common stock and ADRs	$	0.6	$	—	$	(0.1	)	$	—	$	—		$	—	$	0.5
Corporate and municipal bonds	3.5		—		0.1			—		—			—		3.6
	$	4.1	$	—	$	—		$	—	$	—		$	—	$	4.1
Liabilities:
Contingent liabilities	$	2.2	$	—	$	0.1		$	1.5	$	(0.7	)	$	—	$	3.1

	Level 3 Financial Assets and Financial Liabilities For the Six Months Ended March 31, 2015
(in millions)	Balances at beginning of period		Realized gains (losses) during period		Unrealized gains (losses) during period			Purchases/issuances		Settlements			Transfers in or (out) of Level 3		Balances at end of period
Assets:
Common stock and ADRs	$	0.7	$	—	$	(0.2	)	$	—	$	—		$	—	$	0.5
Corporate and municipal bonds	3.6		—		—			—		—			—		3.6
	$	4.3	$	—	$	(0.2	)	$	—	$	—		$	—	$	4.1
Liabilities:
Contingent liabilities	$	5.5	$	—	$	0.2		$	1.5	$	(4.1	)	$	—	$	3.1