Real Estate Transactions (Details) - Discontinued Operations, Disposed of by Sale - The ACS Center ft² in Thousands, $ in Millions	Jun. 15, 2017 USD ($) ft²
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Area of property (in sq ft) \| ft²	996
Gross sales price of property sold	$ 166.0
Gain from sale of business	$ 119.8

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.

No definition available.

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