ACQUISITIONS, GOODWILL, AND ACQUIRED INTANGIBLE ASSETS Assets Acquired and Liabilities Assumed (Details) - USD ($) $ in Thousands			6 Months Ended		12 Months Ended
	Jun. 25, 2018	Feb. 12, 2018	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Purchase Price
Cash paid, net of cash acquired			$ 12,912	$ 0	$ 12,912	$ (28)
Allocation
Goodwill			22,058		22,058		$ 14,698
Less: accumulated amortization of acquired intangible assets			(12,494)		(12,494)		(10,442)
Total acquired intangible assets, net			26,343		26,343		$ 7,337
Mac Warehouse, LLC
Purchase Price
Cash paid, net of cash acquired	$ 1,143
Allocation
Accounts receivable, net	399
Inventories, net	1,772
Prepaids and other current assets	29
Fixed assets	154
Intangibles	2,763
Accounts payable	(682)
Accrued liabilities	(223)
Long-term debt, net	(3,069)
Total net assets, net of cash acquired	$ 1,143
Mac Warehouse, LLC | Customer relationships
Allocation
Useful life	1 year 6 months
tZero.com, Inc. | Verify Investor, LLC
Purchase Price
Cash paid, net of cash acquired		$ 11,769
Allocation
Intangibles		7,400	7,400		7,400
Goodwill		7,360
Other assets acquired		3
Other liabilities assumed		(179)
Total net assets, net of cash acquired		14,584
Less: noncontrolling interest		(2,815)
Total net assets attributable to tZERO, net of cash acquired		$ 11,769
Less: accumulated amortization of acquired intangible assets			(313)		(313)
Total acquired intangible assets, net			7,087		7,087
tZero.com, Inc. | Verify Investor, LLC | Technology and developed software
Allocation
Finite-lived intangible assets acquired			6,300		6,300
Useful life		10 years
tZero.com, Inc. | Verify Investor, LLC | Trade names
Allocation
Finite-lived intangible assets acquired			700		700
Useful life		10 years
tZero.com, Inc. | Verify Investor, LLC | Customer relationships
Allocation
Finite-lived intangible assets acquired			$ 400		$ 400
Useful life		6 months