Equity - Common Stock (Details) - USD ($)		3 Months Ended
	Apr. 17, 2015	Mar. 31, 2017	Mar. 31, 2016
Class of Stock [Line Items]
Common stock share price (in dollars per share)		$ 23.16
Issuance of common stock, net		$ 3,740,000	$ 0
ATM Program
Class of Stock [Line Items]
Issuance of common stock, net		$ 3,900,000
Maximum aggregate offering amount	$ 125,000,000
Common stock, shares, issued (in shares)		168,685
Net proceeds from issuance of common stock		$ 3,800,000
Shares available under ATM (in shares)		$ 111,800,000