Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended		12 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Cash flows from operating activities:
Consolidated net income	$ 1,357	$ 7,496	$ 2,662	$ 76,946
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Depreciation and amortization	17,827	12,806	23,085	16,495
Stock-based compensation to employees and directors	2,577	2,949	3,663	3,823
Deferred income taxes	3,470	2,909	4,302	(65,611)
Amortization of debt issuance costs	21	0	21	4
Loss on investment in precious metals	662	752	1,179	1,734
Loss on investment in cryptocurrency	147	50	147	50
Restructuring reversals	0	(360)	0	(360)
Ineffective portion of loss on cash flow hedge	124	0	124	0
Other	9	(11)	(38)	(16)
Changes in operating assets and liabilities, net of acquisitions:
Restricted cash	0	0	1,000	75
Accounts receivable, net	2,662	1,106	(1,360)	(269)
Inventories, net	3,002	1,760	2,077	(2,550)
Prepaid inventories, net	1,936	81	445	203
Prepaids and other current assets	(3,782)	(3,484)	(1,753)	(1,025)
Other long-term assets, net	380	(7)	413	440
Accounts payable	(47,313)	(27,512)	1,851	8,447
Accrued liabilities	(17,751)	(3,164)	1,020	17,103
Deferred revenue	(3,298)	3,330	4,502	10,793
Other long-term liabilities	1,570	803	1,590	3,083
Net cash (used in) provided by operating activities	(36,400)	(496)	44,930	69,365
Cash flows from investing activities:
Purchases of marketable securities	(11)	(19)	(15)	(40)
Sales of marketable securities	35	77	35	78
Purchases of intangible assets	(187)	(54)	(268)	(54)
Investment in precious metals	0	0	(2,496)	(2,100)
Investment in cryptocurrency	0	(396)	96	(396)
Equity method investment	(152)	0	(402)	0
Disbursements for loans	(5,000)	0	(5,000)	0
Cost method investments	(7,000)	0	(7,000)	0
Acquisitions of businesses, net of cash acquired	(10,573)	0	(10,573)	0
Expenditures for fixed assets, including internal-use software and website development	(43,381)	(32,544)	(52,183)	(36,641)
Proceeds from sale of fixed assets	30	0	73	0
Net cash used in investing activities	(66,239)	(32,936)	(77,733)	(39,153)
Cash flows from financing activities:
Payments on capital lease obligations	(362)	(325)	(362)	(325)
Paydown on direct financing arrangement	(229)	(209)	(302)	(275)
Change in restricted cash	75	0	75	125
Proceeds from exercise of stock options	270	342	439	444
Purchase of treasury stock	(2,367)	(2,301)	(2,367)	(2,303)
Proceeds from debt issuance	5,500	0	5,500	0
Payment of debt issuance costs	(621)	0	(1,652)	0
Net cash provided by (used in) financing activities	2,266	(2,493)	1,331	(2,334)
Net (decrease) increase in cash and cash equivalents	(100,373)	(35,925)	(31,472)	27,878
Cash and cash equivalents, beginning of period	181,641	148,665	112,740	84,862
Cash and cash equivalents, end of period	81,268	112,740	81,268	112,740
Cash paid during the period:
Interest paid	35	37	45	52
Taxes paid	272	36	312	267
Non-cash investing and financing activities:
Fixed assets, including internal-use software and website development, costs financed through accounts payable and accrued liabilities	1,414	505	1,414	635
Equipment acquired under capital lease obligations	362	325	362	325
Capitalized interest cost	117	0	143	0
Acquisition of businesses through stock issuance	18,149	0	18,149	0
Change in value of cash flow hedge	$ 1,684	$ 0	$ 2,692	$ 0