Merger Agreement Merger (Narrative) Details - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Business Acquisition [Line Items]
Merger agreement date			Jun. 02, 2015
Merger share exchange ratio	0.5231		0.5231
Ownership percentage after merger			40.00%
Merger agreement termination fees	$ 15,700		$ 15,700
Merger-related costs	3,262	$ 0	$ 3,469	$ 0
BMC [Member]
Business Acquisition [Line Items]
Ownership percentage after merger			60.00%
Merger agreement termination fees	$ 23,600		$ 23,600

Amount payable to the other party upon termination of the merger agreement under certain circumstances.

No definition available.

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Namespace Prefix:	stck_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

This element represents merger-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Number of shares of the registrants stock that each share of the target company’s stock will be converted into in conjunction with a merger.

+ References

No definition available.

+ Details

Name:	stck_MergerShareExchangeRatio
Namespace Prefix:	stck_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Percentage of stock owned after closing of merger transaction.

+ References

No definition available.

+ Details

Name:	stck_StockPercentageOfOwnershipAfterMerger
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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Date when the business acquisition agreement was executed, in CCYY-MM-DD format.

+ References

No definition available.

+ Details

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Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Period Type:	duration

- Details

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