Real Estate and Intangibles - Proforma Financial Information of Future Operating Results (Detail Parenthetical) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015
ICE – Albuquerque and NPS – Omaha and DEA – Birmingham and FBI – Birmingham and EPA – Kansas City and FBI – Albany and AOC – South Bend [Member]
Real Estate Properties [Line Items]
Property acquisition costs	$ 1.8
DOE - Lakewood and AOC - Aberdeen and ICE - Otay and DEA - Pleasanton and USCIS - Lincoln and DEA - Dallas Lab and FBI - Richmond [Member]
Real Estate Properties [Line Items]
Property acquisition and formation costs		$ 4.6

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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