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Consolidated Statements of Equity (Parenthetical) - shares	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017	Dec. 31, 2016
Balance (in units/ shares)	102,150,358	99,390,234	101,292,299	98,498,651
Conversion of common units to common shares (in units/shares)	53,817	185,000
Share-based compensation issuance, net of redemptions (in units/shares)	127,242	159,801
Forward Equity Sale Agreement
Common shares issued during the period (in shares)	677,000
Common Shares | Common Stock Issued to Public Under At-the-Market Program
Common shares issued during the period (in shares)		546,782

X

- Definition

Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

+ References

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The number of shares issued during the period upon the conversion of units. An example of a convertible unit is an umbrella partnership real estate investment trust unit (UPREIT unit).

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Number of new stock issued during the period.

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