Company Owned Life Insurance Policies - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Mar. 31, 2013	Mar. 31, 2013
Life Insurance Policies [Line Items]
Gain on settlement of insurance policies		$ 3,993
Amount of proceed received from life insurance policies	$ 18,102

The cash inflow for proceeds from life insurance policies for which the entity is the beneficiary.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 12

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3179-108585

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

-URI http://asc.fasb.org/extlink&oid=6516133

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