Environmental Matters - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	Jun. 30, 2014
Accrual For Environmental Loss Contingencies [Roll Forward]
Third-party escrow funds, state funds or insurance	$ 1.4

Recorded amount of the individual components comprising the asset for third-party recoveries related to environmental remediation obligations.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 410

-SubTopic 30

-Section 50

-Paragraph 7

-URI http://asc.fasb.org/extlink&oid=6393242&loc=d3e13207-110859

Name:	us-gaap_RecordedThirdPartyEnvironmentalRecoveriesAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant