The cash inflow from the sale of formerly productive land held for sale, anything permanently fixed to it, including buildings, structures on it, and so forth.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3179-108585

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

Asset Held for Sale - Additional Information (Detail) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended
	Aug. 31, 2017	Mar. 31, 2018	Dec. 31, 2017	Jul. 31, 2016
Asset Held For Sale Current [Abstract]
Net book value of airport facility reclassified as an assets held for sale, current			$ 1,501	$ 1,500
Sale price of airport facility	$ 1,500
Fees related to sale of airport facility	$ 200
Sale of airport facility date		2018-01