Inventories (Details) (USD $) In Thousands, unless otherwise specified	Jan. 31, 2015	Apr. 30, 2014	Jan. 31, 2014
Inventories [Abstract]
Finished goods	$ 48,212us-gaap_InventoryFinishedGoods	$ 62,071us-gaap_InventoryFinishedGoods	$ 62,460us-gaap_InventoryFinishedGoods
Work-in-process	6,884us-gaap_InventoryWorkInProcess	6,041us-gaap_InventoryWorkInProcess	6,875us-gaap_InventoryWorkInProcess
Paper, cloth, and other	5,485us-gaap_OtherInventoryPurchasedGoods	5,476us-gaap_OtherInventoryPurchasedGoods	7,088us-gaap_OtherInventoryPurchasedGoods
Gross inventory	60,581us-gaap_InventoryGross	73,588us-gaap_InventoryGross	76,423us-gaap_InventoryGross
Inventory value of estimated sales returns	9,538us-gaap_InventoryAdjustments	6,774us-gaap_InventoryAdjustments	8,797us-gaap_InventoryAdjustments
LIFO reserve	(5,092)us-gaap_InventoryLIFOReserve	(4,867)us-gaap_InventoryLIFOReserve	(6,052)us-gaap_InventoryLIFOReserve
Total inventories	$ 65,027us-gaap_InventoryNet	$ 75,495us-gaap_InventoryNet	$ 79,168us-gaap_InventoryNet

Certain changes made in the current period to the value and amount of inventory reported.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.6(b))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 6

-Subparagraph b

-Article 5

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 330

-SubTopic 10

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- Definition

Amount before valuation and LIFO reserves of completed merchandise or goods expected to be sold within one year or operating cycle, if longer.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 6

-Subparagraph a

-Article 5

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.6(a)(1))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Gross amount, as of the balance sheet date, of merchandise, goods, commodities, or supplies held for future sale or to be used in manufacturing, servicing or production process.

+ References

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- Definition

Amount of difference between inventory at lower of LIFO cost or market and inventory at lower of other inventory accounting method cost or market, for example, but not limited to, FIFO or average cost.

+ References

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- Definition

Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.6(a))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 330

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

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-Section 45

-Paragraph 1

-Subparagraph (b)

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- Definition

Amount before valuation and LIFO reserves of merchandise or goods in the production process expected to be completed within one year or operating cycle, if longer.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 6

-Subparagraph a

-Article 5

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.6(a)(3))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Gross amount of components used by the entity which are bought from another entity rather than produced by the entity.

+ References

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