Consolidated funded indebtedness ratio.

No definition available.

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- Definition

Debt instrument calculation of make whole amount description.

+ References

No definition available.

+ Details

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- Definition

Debt instrument permitted minimum aggregate principal amount prepayment without penalty.

+ References

No definition available.

+ Details

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- Definition

Discount on senior notes principal and interest, percentage.

+ References

No definition available.

+ Details

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- Definition

Interest coverage ratio minimum.

+ References

No definition available.

+ Details

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- Definition

Letter of credit maximum capacity.

+ References

No definition available.

+ Details

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- Definition

Number of tranches.

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No definition available.

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- Definition

Percentage of face value to be paid if notes are prepaid.

+ References

No definition available.

+ Details

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 2

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-Topic 835

-SubTopic 30

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

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-Paragraph 2

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-Name Regulation S-X (SX)

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-Subparagraph (SX 210.5-02.22(a)(1))

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- Definition

Description of the payment terms of the debt instrument (for example, whether periodic payments include principal and frequency of payments) and discussion about any contingencies associated with the payment.

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(3))

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- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.16)

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-Name Regulation S-X (SX)

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-Subparagraph (SX 210.7-03.16)

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- Definition

The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

+ References

No definition available.

+ Details

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- Definition

Date the credit facility terminates, in CCYY-MM-DD format.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

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-Subparagraph (SX 210.5-02.19(b),22(b))

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- Definition

Description of the interest rate for the amounts borrowed under the credit facility, including the terms and the method for determining the interest rate (for example, fixed or variable, LIBOR plus a percentage, increasing rate, timing of interest rate resets, remarketing provisions).

+ References

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

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Period Type:	instant

- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

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Period Type:	instant

- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

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- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

+ References

No definition available.

+ Details

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- Definition

The cash outflow for a borrowing supported by a written promise to pay an obligation.

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-Publisher FASB

-Name Accounting Standards Codification

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Indebtedness - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	0 Months Ended	12 Months Ended	97 Months Ended	78 Months Ended	1 Months Ended
	Oct. 30, 2014	Mar. 31, 2015	Mar. 31, 2015	Mar. 31, 2013	Oct. 31, 2014	Mar. 31, 2014	Nov. 15, 2005 Loan	Oct. 02, 2007 Loan
Debt Instrument [Line Items]
Senior notes, permitted minimum aggregate principal amount prepayment without penalty		10.00%
Percentage of face value to be paid if notes are prepaid		100.00%exp_ValueOfDebtInstrumentIfPrepaid
Senior notes, calculation of make-whole amount, description		Discounting the remaining scheduled payments of interest and principal of the Senior Notes being prepaid at a discount rate equal to the sum of 50 basis points
Discount on senior notes principal and interest		0.50%
Interest coverage ratio	250.00%exp_InterestCoverageRatioMinimum
Unused line of credit commitment fee based on leverage ratio	0.10%
Borrowings outstanding under Credit Facility		$ 330.0us-gaap_LineOfCredit	$ 330.0us-gaap_LineOfCredit
Bank credit facility, borrowings available		160.8	160.8
Letter of credit facility		50.0exp_LetterOfCreditMaximumCapacity	50.0exp_LetterOfCreditMaximumCapacity
Letters of credit outstanding, amount		9.2	9.2
Maximum [Member]
Debt Instrument [Line Items]
Consolidated funded indebtedness ratio	350.00%
Unused line of credit commitment fee based on leverage ratio	0.35%
London Interbank Offered Rate (LIBOR) [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Variable margin	1.00%
London Interbank Offered Rate (LIBOR) [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Variable margin	2.25%
Federal Funds Effective Swap Rate \| Minimum [Member]
Debt Instrument [Line Items]
Variable margin	0.00%
Federal Funds Effective Swap Rate \| Maximum [Member]
Debt Instrument [Line Items]
Variable margin	1.25%
Bank Credit Facility [Member]
Debt Instrument [Line Items]
Weighted-average interest rate		1.50%	1.50%	2.00%		1.90%
Interest rate of debt instrument		1.60%	1.60%			1.50%
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Credit facility, principal balance	500.0
Credit facility, maturity date	Oct. 31, 2019
Credit facility, interest rate description		At the option of the Company, outstanding principal amounts on the Amended Credit Facility bear interest at a variable rate equal to (i) LIBOR, plus an agreed margin (ranging from 100 to 225 basis points), which is to be established quarterly based upon the Company’s ratio of consolidated EBITDA, defined as earnings before interest, taxes, depreciation and amortization, to the Company’s consolidated indebtedness (the “Leverage Ratio”), or (ii) an alternative base rate which is the higher of (a) the prime rate or (b) the federal funds rate plus 1/2% per annum plus an agreed margin (ranging from 0 to 125 basis points). Interest payments are payable, in the case of loans bearing interest at a rate based on the federal funds rate, quarterly, or in the case of loans bearing interest at a rate based on LIBOR, at the end of the LIBOR advance periods, which can be a period of up to nine months at the option of the Company. The Company is also required to pay a commitment fee on unused available borrowings under the Amended Credit Facility ranging from 10 to 35 basis points depending upon the Leverage Ratio.
Revolving Credit Facility [Member] \| Scenario, Previously Reported
Debt Instrument [Line Items]
Credit facility, principal balance	400.0
Credit facility, maturity date	Dec. 15, 2015
Line of Credit \| Federal Funds Effective Swap Rate \| Maximum [Member]
Debt Instrument [Line Items]
Variable margin	0.50%
Letter of Credit [Member]
Debt Instrument [Line Items]
Bank credit facility, one-time fee		0.125%
Senior Notes [Member]
Debt Instrument [Line Items]
Weighted-average interest rate		5.81%	5.81%	5.81%		5.81%
Interest rate of debt instrument		5.80%	5.80%			5.81%
2005 Note Purchase Agreement [Member]
Debt Instrument [Line Items]
Senior notes, sale							200.0
Number of tranches							3
Senior notes, repurchased amount			81.1
Senior notes, payment terms		Interest for each tranche of Notes is payable semi-annually on May 15 and November 15 of each year until all principal is paid for the respective tranche.
2007 Note Purchase Agreement [Member]
Debt Instrument [Line Items]
Senior notes, sale								200.0
Number of tranches								4
Senior notes, repurchased amount				122.0
Senior notes, payment terms		Interest for each tranche of Notes is payable semi-annually on April 2 and October 2 of each year until all principal is paid for the respective tranche.
2007 Note Purchase Agreement [Member] \| Series 2007A Tranche A [Member]
Debt Instrument [Line Items]
Repayment of senior note					$ 9.5