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

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

No definition available.

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- Definition

Carrying amount as of the balance sheet date of investments in land and buildings held for sale, excluding real estate considered to be inventory of the entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.1(f))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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Summary of Significant Accounting Policies - Property, Equipment and Capitalized Software Costs (Details) - USD ($) $ in Millions	1 Months Ended	12 Months Ended
	Feb. 28, 2018	Dec. 31, 2017
Corporate Administrative Office Building [Member]
Property Plant And Equipment [Line Items]
Carrying value of property		$ 1.6
Corporate Administrative Office Building [Member] \| Subsequent Event [Member]
Property Plant And Equipment [Line Items]
Proceeds from sale of property	$ 1.8
Minimum [Member]
Property Plant And Equipment [Line Items]
Property, equipment and capitalized software, useful life		1 year
Minimum [Member] \| Capitalized Software [Member]
Property Plant And Equipment [Line Items]
Property, equipment and capitalized software, useful life		2 years
Maximum [Member]
Property Plant And Equipment [Line Items]
Property, equipment and capitalized software, useful life		30 years
Maximum [Member] \| Capitalized Software [Member]
Property Plant And Equipment [Line Items]
Property, equipment and capitalized software, useful life		5 years