Consolidated Statements Of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Net cash flows from operating activities:
Net income	$ 252,111	$ 199,025	$ 362,193
Adjustments to reconcile net income to net cash provided by (used for) operations:
Deferred income tax provision	134,016	126,885	70,047
Depreciation and amortization of property, equipment and leasehold improvements	164,067	124,977	111,175
Other amortization	8,006	14,767	27,789
Share-based compensation	74,087	109,838	87,309
Provision for doubtful accounts	20,168	69,907	13,945
Net securities gains	(62,957)	(30,394)	(243,957)
Income related to associated companies	(185,998)	(228,769)	(211,221)
Distributions from associated companies	223,658	176,491	137,098
Net (gains) losses related to property and equipment, and other assets	29,776	(27,784)	94,074
Gain on disposal of discontinued operations	(7,836)	(12,566)	(10,106)
Change in estimated litigation reserve	(96,500)	101,710	0
Net change in:
Cash and securities segregated and on deposit for regulatory purposes or deposited with clearing and depository organizations	2,691,028	166,108	113,754
Trading assets	1,380,230	(3,223,327)	(383,682)
Investments in managed funds	(295,342)	(80,247)	2,674
Securities borrowed	(127,060)	(1,497,438)	(41,678)
Securities purchased under agreements to resell	56,377	(200,568)	(156,197)
Receivables from brokers, dealers and clearing organizations	551,021	11,872	336,263
Receivables from customers of securities operations	58,233	(349,767)	225
Other receivables	(145,634)	(161,415)	(93,690)
Other assets	83,414	(107,028)	23,488
Trading liabilities	(2,011,277)	1,832,930	(2,511,777)
Securities loaned	420,929	95,607	600,539
Securities sold under agreements to repurchase	(688,355)	(84,303)	2,794,412
Payables to brokers, dealers and clearing organizations	486,841	968,615	(507,722)
Payables to customers of securities operations	(3,455,080)	1,089,423	(249,305)
Trade payables, expense accruals and other liabilities	(225,711)	(3,546)	345,345
Other	(93,967)	(68,163)	(8,655)
Net cash provided by (used for) operating activities	(761,755)	(987,160)	702,340
Net cash flows from investing activities:
Acquisitions of property, equipment and leasehold improvements, and other assets	(295,894)	(600,837)	(166,129)
Proceeds from disposals of property and equipment, and other assets	22,820	52,011	24,400
Proceeds from disposal of discontinued operations, net of expenses and cash of operations sold	5,842	223,217	20,997
Cash acquired upon acquisition of Jefferies Group LLC	0	0	3,017,958
Acquisitions, net of cash acquired	0	(61,493)	0
Cash paid and cash of real estate operations sold to HomeFed Corporation	0	(19,730)	0
Advances on notes, loans and other receivables	(420,219)	(8,500)	(1,934)
Collections on notes, loans and other receivables	153,004	22,002	18,852
Loans to and investments in associated companies	(1,492,060)	(2,959,689)	(2,388,540)
Capital distributions and loan repayment from associated companies	1,389,262	2,756,320	2,381,145
Deconsolidation of asset management entities	(16,512)	(207,965)	0
Purchases of investments (other than short-term)	(873,831)	(1,821,635)	(3,789,166)
Proceeds from maturities of investments	379,629	1,191,349	2,368,734
Proceeds from sales of investments	1,931,656	1,878,427	1,838,029
Other	(2,532)	5,606	(724)
Net cash provided by investing activities	781,165	449,083	3,323,622
Net cash flows from financing activities:
Issuance of debt, net of issuance costs	363,595	1,002,636	2,038,226
Change in short-term borrowings	298,659	0	(88,000)
Reduction of debt	(1,316,494)	(434,278)	(1,894,301)
Net proceeds from other secured financings	205,231	470,415	114,711
Issuance of common shares	1,223	2,190	5,557
Cash and cash equivalents of Crimson Wine Group, Ltd., which was spun off	0	0	(21,042)
Net contributions from (distributions to) redeemable noncontrolling interests	5,165	(2,765)	(8,073)
Distributions to noncontrolling interests	(7,277)	(7,797)	(355,086)
Contributions from noncontrolling interests	15,469	54,259	65,870
Purchase of common shares for treasury	(125,754)	(75,728)	(40,024)
Dividends paid	(92,550)	(93,071)	(91,335)
Other	750	1,921	2,990
Net cash provided by (used for) financing activities	(651,983)	917,782	(270,507)
Effect of foreign exchange rate changes on cash	(5,554)	(10,525)	6,180
Net increase (decrease) in cash and cash equivalents	(638,127)	369,180	3,761,635
Cash and cash equivalents at January 1, including cash classified as assets of discontinued operations	4,276,775	3,907,595	145,960
Cash and cash equivalents at December 31, including cash classified as assets of discontinued operations	3,638,648	4,276,775	3,907,595
Supplemental disclosures of cash flow information:
Interest	980,266	1,038,201	722,695
Income tax payments, net	510	9,880	75,925
Non-cash investing activities:
Common stock issued for acquisition of Jefferies Group LLC	0	0	3,385,699
Issuance of mandatorily redeemable convertible preferred shares for acquisition of Jefferies Group LLC	0	0	125,000
Non-cash financing activities:
Net assets excluding cash and cash equivalents of Crimson Wine Group, Ltd., which was spun off	0	0	175,958
Issuance of common shares for debt conversion	$ 0	$ 97,546	$ 0