Common Shares (Tables) (2012 ATM Program [Member])

9 Months Ended

Sep. 30, 2014

2012 ATM Program [Member]

Activity Under At-The-Market Share Offering Program

The following table presents activity under our 2012 ATM program for the three and nine months ended September 30, 2014 and 2013.

	Three Months Ended				Nine Months Ended
	September 30,				September 30,
(in thousands, except per share amounts)	2014		2013		2014		2013
Total net consideration	$	50,535.3	$	—	$	50,535.3	$	40,097.6
Common shares sold	688.3		—		688.3		555.1
Average price per share	$	74.60	$	—	$	74.60	$	73.73