Shareholders' Equity Shareholders' Equity (Details) - USD ($) $ in Thousands, shares in Millions	6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015
Class of Stock [Line Items]
Proceeds from Issuance of Common Stock	$ 99,844	$ 4,756
At-the-market equity issuance [Member]
Class of Stock [Line Items]
Stock Issued During Period, Shares, New Issues	4.2
Proceeds from Issuance of Common Stock	$ 98,500
Gross Proceeds [Member] | At-the-market equity issuance [Member]
Class of Stock [Line Items]
Proceeds from Issuance of Common Stock	$ 99,600