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Aggregate value of stock related to stock performance issued during the period.

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Amount of other increase (decrease) in additional paid in capital (APIC).

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This element represents the amount of recognized equity-based compensation during the period, that is, the amount recognized as expense in the income statement (or as asset if compensation is capitalized). Alternate captions include the words "stock-based compensation".

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Amount of increase in additional paid in capital (APIC) resulting from a tax benefit associated with share-based compensation plan other than an employee stock ownership plan (ESOP). Includes, but is not limited to, excess tax benefit.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount after tax of (increase) decrease in the value of the projected benefit obligation related to a change in an actuarial assumption and increase (decrease) in the value of the plan assets resulting from experience different from that assumed, that has not been recognized in net periodic benefit (cost) credit.

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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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Value of stock related to Restricted Stock Awards issued during the period, net of the stock value of such awards forfeited.

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Supplemental Condensed Consolidating Financial Statements (Details 3) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Jan. 03, 2015	Oct. 04, 2014	Jul. 05, 2014	Apr. 05, 2014	Jan. 04, 2014	Sep. 28, 2013	Jun. 29, 2013	Mar. 30, 2013	Jan. 03, 2015	Jan. 04, 2014	Dec. 29, 2012
Supplemental Statement Of Stockholders' Equity [Abstract]
Balance				$ (5,898)us-gaap_StockholdersEquity				$ (20,592)us-gaap_StockholdersEquity	$ (5,898)us-gaap_StockholdersEquity	$ (20,592)us-gaap_StockholdersEquity	$ 8,374us-gaap_StockholdersEquity
Net (loss) income	(7,640)us-gaap_NetIncomeLoss	(860)us-gaap_NetIncomeLoss	3,236us-gaap_NetIncomeLoss	(8,608)us-gaap_NetIncomeLoss	(2,457)us-gaap_NetIncomeLoss	(3,206)us-gaap_NetIncomeLoss	(22,306)us-gaap_NetIncomeLoss	(12,649)us-gaap_NetIncomeLoss	(13,872)us-gaap_NetIncomeLoss	(40,618)us-gaap_NetIncomeLoss	(23,027)us-gaap_NetIncomeLoss
Foreign currency translation adjustment, net of tax									(481)	(161)	103
Unrealized (loss) income from pension plan, net of taxes									(17,651)	13,910	(8,245)
Issuance of restricted stock, net of forfeitures									18	6	19
Issuance of performance shares									10	6
Issuance of stock related to the rights offerings, net of expenses									0	38,613
Compensation related to share-based grants									2,896	6,117	2,730
Impact of net settled shares for vested grants									(963)	(3,193)	(526)
Excess tax benefits from share-based compensation arrangements									(16)	16
Other									(69)	(2)	(20)
Net transactions with Parent									0bxc_NetTransactionsWithParent	0bxc_NetTransactionsWithParent	0bxc_NetTransactionsWithParent
Balance	(36,026)us-gaap_StockholdersEquity				(5,898)us-gaap_StockholdersEquity				(36,026)us-gaap_StockholdersEquity	(5,898)us-gaap_StockholdersEquity	(20,592)us-gaap_StockholdersEquity
BlueLinx Holdings Inc.
Supplemental Statement Of Stockholders' Equity [Abstract]
Balance				(5,898)				(20,592)	(5,898)	(20,592)	8,374
Net (loss) income									(13,872)	(40,618)	(23,027)
Foreign currency translation adjustment, net of tax									(481)	(161)	103
Unrealized (loss) income from pension plan, net of taxes									(17,651)	13,910	(8,245)
Issuance of restricted stock, net of forfeitures									18	6	19
Issuance of performance shares									10	6
Issuance of stock related to the rights offerings, net of expenses									0	38,613
Compensation related to share-based grants									2,896	6,117	2,730
Impact of net settled shares for vested grants									(963)	(3,193)	(526)
Excess tax benefits from share-based compensation arrangements									(16)	16
Other									(69)	(2)	(20)
Net transactions with Parent									0	0	0
Balance	(36,026)				(5,898)				(36,026)	(5,898)	(20,592)
BlueLinx Corporation and Subsidiaries
Supplemental Statement Of Stockholders' Equity [Abstract]
Balance				49,039				40,603	49,039	40,603	83,626
Net (loss) income									(23,534)	(49,205)	(37,237)
Foreign currency translation adjustment, net of tax									(481)	(161)	103
Unrealized (loss) income from pension plan, net of taxes									(17,651)	13,910	(8,245)
Issuance of restricted stock, net of forfeitures									0	6	19
Issuance of performance shares									0	6
Issuance of stock related to the rights offerings, net of expenses									0	0
Compensation related to share-based grants									0	0	0
Impact of net settled shares for vested grants									0	0	0
Excess tax benefits from share-based compensation arrangements									0	0
Other									0	0	0
Net transactions with Parent									1,301	43,880	2,337
Balance	8,674				49,039				8,674	49,039	40,603
LLC Subsidiaries
Supplemental Statement Of Stockholders' Equity [Abstract]
Balance				(96,774)				(107,656)	(96,774)	(107,656)	(124,175)
Net (loss) income									15,000	14,343	18,536
Foreign currency translation adjustment, net of tax									0	0	0
Unrealized (loss) income from pension plan, net of taxes									0	0	0
Issuance of restricted stock, net of forfeitures									0	0	0
Issuance of performance shares									0	0
Issuance of stock related to the rights offerings, net of expenses									0	0
Compensation related to share-based grants									0	0	0
Impact of net settled shares for vested grants									0	0	0
Excess tax benefits from share-based compensation arrangements									0	0
Other									0	0	0
Net transactions with Parent									(5,164)	(3,461)	(2,017)
Balance	(86,938)				(96,774)				(86,938)	(96,774)	(107,656)
Eliminations
Supplemental Statement Of Stockholders' Equity [Abstract]
Balance				47,735				67,053	47,735	67,053	40,549
Net (loss) income									8,534	34,862	18,701
Foreign currency translation adjustment, net of tax									481	161	(103)
Unrealized (loss) income from pension plan, net of taxes									17,651	(13,910)	8,245
Issuance of restricted stock, net of forfeitures									0	(6)	(19)
Issuance of performance shares									0	(6)
Issuance of stock related to the rights offerings, net of expenses									0	0
Compensation related to share-based grants									0	0	0
Impact of net settled shares for vested grants									0	0	0
Excess tax benefits from share-based compensation arrangements									0	0
Other									0	0	0
Net transactions with Parent									3,863	(40,419)	(320)
Balance	$ 78,264				$ 47,735				$ 78,264	$ 47,735	$ 67,053