Interest Rate Derivative - Additional Information (Detail) (Interest rate swap, USD $) In Thousands, unless otherwise specified	6 Months Ended
Jun. 30, 2011
Interest rate swap
Derivative [Line Items]
Interest rate swap, notional amount	$ 5,850
Interest rate swap, date entered	Sep. 30, 2008
Interest rate swap, maturity date	Sep. 30, 2028
Interest rate for the term loan	4.50%

Total monetary amount specified by the derivative liability (or liabilities). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=6935481&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Notional Amount
-URI http://asc.fasb.org/extlink&oid=6519104

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=6935481&loc=SL5579245-113959

Name:	us-gaap_DerivativeLiabilityNotionalAmount
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	instant