Discontinued Operations - Additional Information (Details) - Cole Capital [Member] - Held-for-sale or Disposed of by Sale [Member] - USD ($)	3 Months Ended
Mar. 31, 2019	Feb. 01, 2018
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Consideration paid at closing		$ 120,000,000.0
Contingent consideration, maximum consideration receivable	$ 80,000,000.0
Net revenue payments received	$ 0

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.

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