Consolidated Statements Of Cash Flows (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011
Net cash flows from operating activities:
Net income (loss)	$ 413,801	$ (94,108)
Adjustments to reconcile net income (loss) to net cash provided by operations:
Deferred income tax provision (benefit)	233,585	(31,009)
Depreciation and amortization of property, equipment and leasehold improvements	77,281	50,102
Other amortization	57,425	22,075
Share-based compensation	10,732	18,843
Excess tax benefit from exercise of stock options		(242)
Provision for doubtful accounts	8,920	157
Net securities gains	(581,669)	(539,215)
(Income) losses related to associated companies	(105,391)	728,440
Distributions from associated companies	77,632	37,454
Net gains related to real estate, property and equipment, and other assets	(5,289)	(92,194)
Income related to Fortescue's Pilbara project, net of proceeds received	107,881	21,994
(Gain) loss on disposal of discontinued operations	7,117	(2,612)
Change in estimated litigation reserve		(2,241)
Net change in:
Trade, notes and other receivables	(32,557)	(6,990)
Inventory	1,495	3,058
Prepaids and other assets	7,116	505
Trade payables and expense accruals	(11,699)	(51,308)
Other liabilities	7,799	(36,259)
Income taxes payable	(9,183)	(7,895)
Other	(1,883)	4,399
Net cash provided by operating activities	263,113	22,954
Net cash flows from investing activities:
Acquisitions of property, equipment and leasehold improvements	(51,161)	(30,889)
Acquisitions of and capital expenditures for real estate investments	(4,885)	(7,768)
Proceeds from disposals of real estate, property and equipment, and other assets	8,779	24,095
Net change in restricted cash	4,769	10,472
Proceeds from disposal of discontinued operations, net of expenses and cash of operations sold	26,611	3,192
Acquisitions, net of cash acquired	(25,232)	(86,206)
Advances on notes and other receivables	(2,907)	(3,650)
Collections on notes, loans and other receivables	16,549	14,348
Investments in associated companies	(2,457)	(560,082)
Capital distributions and loan repayment from associated companies	464,162	292,543
Purchases of investments (other than short-term)	(1,114,280)	(2,896,466)
Proceeds from maturities of investments	245,194	344,014
Proceeds from sales of investments	1,363,132	2,780,148
Other	1,650	3,498
Net cash provided by (used for) investing activities	929,924	(112,751)
Net cash flows from financing activities:
Issuance of debt, net of issuance costs	1,022	99,737
Reduction of debt	(571,551)	(144,183)
Issuance of common shares		7,126
Distributions to redeemable noncontrolling interests	(12,722)
Excess tax benefit from exercise of stock options		242
Other	(6,132)	(8,195)
Net cash used for financing activities	(589,383)	(45,273)
Net increase (decrease) in cash and cash equivalents	603,654	(135,070)
Cash and cash equivalents at January 1,	168,490	441,340
Cash and cash equivalents at September 30,	772,144	306,270
Supplemental disclosures of cash flow information:
Interest	99,253	110,654
Income tax payments, net	$ 36,620	$ 24,417