The capitalized costs incurred during the period (excluded from amortization) to purchase, lease or otherwise acquire an unproved property, including costs of lease bonuses and options to purchase or lease properties, the portion of costs applicable to minerals when land including mineral rights is purchased in fee, brokers' fees, recording fees, legal costs, and other costs incurred in acquiring properties.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 932

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-10.(c)(7)(ii))

-URI http://asc.fasb.org/extlink&oid=21918352&loc=d3e511914-122862

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 10

-Paragraph c

-Subparagraph 3(ii)(A)

-Article 4

Name:	us-gaap_AcquisitionCosts
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Acquisition - Additional Information (Detail) (USD $)	3 Months Ended	6 Months Ended
Acquisition - Additional Information (Detail) (USD $)	Sep. 30, 2012	Sep. 30, 2012	Nov. 30, 2012
Business Acquisition [Line Items]
Purchase price			$ 450,699,000
Final Working Capital Adjustment			2,734,000
Direct acquisition cost	$ 6,100,000	$ 6,100,000
Asset Purchase Agreement [Member] \| Cement [Member]
Business Acquisition [Line Items]
Number of business assets acquired			2
Asset Purchase Agreement [Member] \| Aggregates Quarries [Member]
Business Acquisition [Line Items]
Number of business assets acquired			2
Asset Purchase Agreement [Member] \| Ready-mix Plants [Member]
Business Acquisition [Line Items]
Number of business assets acquired			8