Subsequent Event (Details) (USD $) In Millions, unless otherwise specified	Sep. 30, 2012
Subsequent Events [Abstract]
Purchase price of four buildings	$ 3.7

The net book value of the asset(s) sold in connection with the sale of the property to another party and lease back to the seller.

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 98

-Section Appendix A

-Paragraph 28, 29

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 40

-Section 55

-Paragraph 52

-URI http://asc.fasb.org/extlink&oid=9155692&loc=d3e51843-112757

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 40

-Section 55

-Paragraph 50

-URI http://asc.fasb.org/extlink&oid=9155692&loc=d3e51831-112757

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 40

-Section 55

-Paragraph 51

-URI http://asc.fasb.org/extlink&oid=9155692&loc=d3e51840-112757

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