Subsequent Event - Additional Information (Detail) (Subsequent Event, Tyngsborough Massachusetts, USD $)	0 Months Ended
Feb. 26, 2015	Feb. 24, 2015
Subsequent Event \| Tyngsborough Massachusetts
Subsequent Events [Line Items]
Purchase Agreement expected period of extension to complete sale		Mar. 27, 2015
Nonrefundable deposit to escrow agent	$ 300,000	$ 100,000

Escrow deposits related to property sales in noncash investing and financing activities.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4332-108586

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4313-108586

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4304-108586

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