Stock repurchase program additional of shares authorized to be repurchased.

No definition available.

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Namespace Prefix:	exp_
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- Definition

Stock repurchase program average price during the period.

+ References

No definition available.

+ Details

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- 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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- Definition

The 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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Period Type:	instant

- 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

Name:	us-gaap_StockRepurchaseProgramRemainingNumberOfSharesAuthorizedToBeRepurchased
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Data Type:	xbrli:sharesItemType
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Period Type:	instant

- Definition

Number of shares that have been repurchased and retired during the period.

+ References

Reference 1: 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 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30

-Article 5

+ Details

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- Details

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Period Type:

Stockholders' Equity - Additional Information (Detail) - $ / shares			3 Months Ended
	Oct. 07, 2015	Sep. 30, 2015	Sep. 30, 2015	Aug. 10, 2015
Equity Class Of Treasury Stock [Line Items]
Number of additional shares authorized to be repurchased				6,782,700
Outstanding authorization shares				7,500,000
Repurchase of shares		110,000	144,000
Shares repurchased average price			$ 74.61
Subsequent Event [Member]
Equity Class Of Treasury Stock [Line Items]
Repurchase of shares	130,000
Shares repurchased average price	$ 70.31
Stock repurchase remaining number of shares authorized to be repurchased	7,116,000