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Percentage of assets and liabilities of parent and wholly owned subsidiaries included in consolidated financial statements.

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Significant accounting policies.

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Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Future cash outflow to pay for purchases of fixed assets that have occurred.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Narrative) (Details) - USD ($) shares in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Significant Accounting Policies [Line Items]
Percentage of parent and wholly-owned subsidiaries assets and liabilities included in financial statements (in Percent)	100.00%
Net book value of capitalized software	$ 17,876,000		$ 17,868,000
Provision for estimated returns	6,432,000	$ 5,175,000
Revenue from shipping and handling charges	1,889,000	$ 828,000
Assets, fair value	$ 28,604,000		24,330,000
Common stock equivalents excluded from weighted average shares outstanding for diluted income per common share purposes (in Shares)	159	555
Payment for income taxes	$ 4,000	$ 0
Payment for interest	45,000	42,000
Non-cash capital additions	793,000	$ 1,290,000
Accounting Standards Update 2015-17 [Member]
Significant Accounting Policies [Line Items]
Reclassification of current deferred income taxes to non-current deferred income taxes			1,642,000
Accounting Standards Update 2016-09 [Member] \| Excess Tax Benefit from Share-based Compensation Recognized Within Income Tax Expense [Member]
Significant Accounting Policies [Line Items]
Excess tax benefit from share-based compensation	1,382,000
Level 2 [Member]
Significant Accounting Policies [Line Items]
Assets, fair value	0		0
Level 3 [Member]
Significant Accounting Policies [Line Items]
Assets, fair value	$ 0		0
Inventory Purchases [Member] \| Major Supplier 1 [Member]
Significant Accounting Policies [Line Items]
Percent concentration risk (in Percent)	12.00%	10.00%
Inventory Purchases [Member] \| Major Supplier 2 [Member]
Significant Accounting Policies [Line Items]
Percent concentration risk (in Percent)	10.00%	13.00%
Fulfillment Cost [Member] \| Third Party Fulfillment Provider Concentration [Member]
Significant Accounting Policies [Line Items]
Percent concentration risk (in Percent)	100.00%
Allowance for Sales Returns [Member]
Significant Accounting Policies [Line Items]
Returns reserve balance	$ 1,818,000		$ 740,000
Minimum [Member]
Significant Accounting Policies [Line Items]
Estimated useful life (in Duration)	2 years
Minimum [Member] \| Direct Shipping Cost [Member] \| Direct Shipping Provider [Member]
Significant Accounting Policies [Line Items]
Percent concentration risk (in Percent)	98.00%
Minimum [Member] \| Retail Shipping Costs [Member] \| Retail Shipping Provider [Member]
Significant Accounting Policies [Line Items]
Percent concentration risk (in Percent)	98.00%
Minimum [Member] \| Internal-Use Software and Website Development [Member]
Significant Accounting Policies [Line Items]
Estimated useful life (in Duration)	2 years
Maximum [Member]
Significant Accounting Policies [Line Items]
Estimated useful life (in Duration)	7 years
Maximum [Member] \| Internal-Use Software and Website Development [Member]
Significant Accounting Policies [Line Items]
Estimated useful life (in Duration)	5 years
Available-for-sale Securities [Member] \| Government and Agency Securities and Corporate Debt Securities [Member] \| Minimum [Member]
Significant Accounting Policies [Line Items]
Short term investments maturities period	3 months
Available-for-sale Securities [Member] \| Government and Agency Securities and Corporate Debt Securities [Member] \| Maximum [Member]
Significant Accounting Policies [Line Items]
Short term investments maturities period	3 years