SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Tables)

6 Months Ended

Jun. 30, 2017

Accounting Policies [Abstract]

Schedule of restructuring charges

The following tables summarize the restructuring charge:

Accrued restructuring charge at December 31, 2016	$	694
Restructuring charge		6,588
Cash paid		(1,788	)
Non-cash items		(2,207	)
Accrued restructuring charge at June 30, 2017	$	3,287

	Three Months Ended June 30, 2017
	Capital Markets		Principal Investments – United Online		Corporate		Total
Restructuring charge:
Employee termination costs	$	2,534	$	109	$	2,182	$	4,825
Facility closure and consolidation charge		1,389		—		—		1,389
Total restructuring charge	$	3,923	$	109	$	2,182	$	6,214

	Six Months Ended June 30, 2017
	Capital Markets		Principal Investments – United Online		Corporate		Total
Restructuring charge:
Employee termination costs	$	2,534	$	483	$	2,182	$	5,199
Facility closure and consolidation charge		1,389		—		—		1,389
Total restructuring charge	$	3,923	$	483	$	2,182	$	6,588

Schedule of securities owned and securities sold not yet purchased at fair value

As of June 30, 2017 and December 31, 2016, the Company’s securities owned and securities sold not yet purchased at fair value consisted of the following securities:

	June 30,		December 31,
	2017		2016
Securities and other investments owned
Common stocks and warrants	$	20,771	$	2,084
Corporate bonds		1,620		1,025
Loan receivable		29,108		—
Partnership interests		26,705		13,470
	$	78,204	$	16,579
Securities sold not yet purchased
Common stocks	$	2,594	$	—
Corporate bonds		932		846
	$	3,526	$	846

Schedule of financial assets and liabilities measured on recurring basis

The following tables present information on the financial assets and liabilities measured and recorded at fair value on a recurring basis as of June 30, 2017 and December 31, 2016.

	Financial Assets and Liabilities Measured at Fair Value on a Recurring Basis at June 30, 2017, Using
	Fair value at June 30, 2017		Quoted prices in active markets identical assets (Level 1)		Other observable inputs (Level 2)		Significant unobservable inputs (Level 3)
Assets:
Securities and other investments owned:
Common stocks and warrants	$	20,771	$	11,008	$	—	$	9,763
Corporate bonds		1,620		—		1,620		—
Loan receivable		29,108		—		—		29,108
Partnership interests		21,726		4,660		44		17,022
Total assets measured at fair value	$	73,225	$	15,668	$	1,664	$	55,893
Liabilities:
Securities sold not yet purchased:
Common stocks	$	2,594	$	2,594	$	—	$	—
Corporate bonds		932		—		932		—
Total securities sold not yet purchased		3,526		2,594		932		—
Mandatorily redeemable noncontrolling interests issued after November 5, 2003		9,641		—		—		9,641
Total liabilities measured at fair value	$	13,167	$	2,594	$	932	$	9,641

	Financial Assets and Liabilities Measured at Fair Value on a Recurring Basis at December 31, 2016, Using
	Fair value at December 31, 2016		Quoted prices in active markets identical assets (Level 1)		Other observable inputs (Level 2)		Significant unobservable inputs (Level 3)
Assets:
Securities and other investments owned:
Common stocks	$	2,084	$	1,785	$	—	$	299
Corporate bonds		1,025		—		865		160
Partnership interests		13,470		—		44		13,426
Total assets measured at fair value	$	16,579	$	1,785	$	909	$	13,885
Liabilities:
Securities sold not yet purchased:
Corporate bonds	$	846	$	—	$	846	$	—
Mandatorily redeemable noncontrolling interests issued after November 5, 2003		3,214		—		—		3,214
Contingent consideration		1,242		—		—		1,242
Total liabilities measured at fair value	$	5,302	$	—	$	846	$	4,456

Schedule of changes in Level 3 fair value hierarchy

The changes in Level 3 fair value hierarchy during the six months ended June 30, 2017 and 2016 are as follows:

	Level 3		Level 3 Changes During the Period												Level 3
	Balance at		Fair			Relating to			Purchases,			Transfer in			Balance at
	Beginning of		Value			Undistributed			Sales and			and/or out			End of
	Period		Adjustments			Earnings			Settlements			of Level 3			Period
Six Months Ended June 30, 2017
Common stocks and warrants	$	299	$	(667	)	$	—		$	10,131		$	—		$	9,763
Corporate bonds		160		—			—			—			(160	)		—
Loan receivable		—		(100	)		—			29,208			—			29,108
Partnership interests		13,426		2,697			—			899			—			17,022
Mandatorily redeemable noncontrolling interests issued after November 5, 2003		3,214		6,250			(272	)		—			449			9,641
Contingent consideration		1,242		8			—			(1,250	)		—			—
Six Months Ended June 30, 2016
Common stocks	$	290	$	(47	)	$	—		$	—		$	—		$	243
Corporate bonds		—		—			—			569			—			569
Partnership interests		1,766		123			418			—			—			2,307
Mandatorily redeemable noncontrolling interests issued after November 5, 2003		2,330		—			(219	)		—			—			2,111
Contingent consideration		2,391		55			—			(1,250	)		—			1,196