Stockholder's Equity (Common Stock Repurchases) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended	9 Months Ended	189 Months Ended
Dec. 27, 2014	Dec. 28, 2013	Dec. 27, 2014	Dec. 28, 2013	Dec. 27, 2014
Stockholders' Equity Note [Abstract]
Common stock purchased (shares)	93,126us-gaap_TreasuryStockSharesAcquired	233,530us-gaap_TreasuryStockSharesAcquired	359,863us-gaap_TreasuryStockSharesAcquired	699,036us-gaap_TreasuryStockSharesAcquired	10,727,227us-gaap_TreasuryStockSharesAcquired
Aggregate purchase price	$ 2,112	$ 6,019	$ 8,048	$ 18,766	$ 400,360
Average purchase price (in dollars per share)	$ 22.68	$ 25.77	$ 22.37	$ 26.85	$ 37.32
Payment related to tax withholding for share-based compensation			$ 1,062	$ 1,483
Shares paid for tax withholding for share-based compensation (shares)			46,130	56,639
Average price per share for shares repurchased from employees for tax payment for share-based compensation			$ 23.01	$ 26.19
Stock repurchase programs, remaining number of shares authorized to be repurchased	772,773		772,773		772,773
Leverage ratio at which common stock repurchases are restricted under Credit Agreement	3.0		3.0		3.0
Leverage ratio under credit agreement	3.1bbox_CreditAgreementActualLeverageRatio		3.1bbox_CreditAgreementActualLeverageRatio		3.1bbox_CreditAgreementActualLeverageRatio

Credit Agreement, Actual Leverage Ratio

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- Definition

Credit Agreement, Leverage Ratio that Restricts Common Stock Repurchases under the Credit Agreement

+ References

No definition available.

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- Definition

Total tax payments made by the entity divided by the total number of shares withheld to satisty employee income taxes.

+ References

No definition available.

+ Details

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- Definition

Amount of cash outflow to satisfy an employee's income tax withholding obligation as part of a net-share settlement of a share-based award.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 15

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3291-108585

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- Definition

For net-share settlement of share-based awards when the employer settles employees' income tax withholding obligations, this element represents the number of shares the employees use to repay the employer.

+ References

No definition available.

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- Definition

The remaining number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

+ References

No definition available.

+ Details

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- Definition

Total cost of shares repurchased divided by the total number of shares repurchased.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 30

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6405813&loc=d3e23239-112655

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- Definition

Number of shares that have been repurchased during the period and are being held in treasury.

+ References

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- Definition

Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 30

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6405813&loc=d3e23239-112655

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