Employee Plans (Tables)

12 Months Ended

Dec. 31, 2017

Employee Service Share Based Compensation Aggregate Disclosures [Abstract]

Summary of Information Regarding the Common Shares Issued Under the ESPP

The following table summarizes information regarding the Common Shares issued under the ESPP (the net proceeds noted below were contributed to ERPOP in exchange for OP Units):

	Year Ended December 31,
	2017		2016		2015
	(Amounts in thousands except share and per share amounts)
Shares issued		68,286		63,909		68,462
Issuance price ranges	$52.79 – $58.06		$51.85 – $63.37		$63.70 – $65.90
Issuance proceeds	$3,744		$3,686		$4,404