Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2016	Dec. 31, 2015
Preferred Stock, Par or Stated Value Per Share (usd per share)	$ 0.01	$ 0.01
Preferred Stock, Shares Authorized (shares)	9,945,539	9,945,539
Preferred Stock, Shares Issued (shares)	0	0
Preferred Stock, Shares Outstanding (shares)	0	0
Common Stock, Par or Stated Value Per Share (usd per share)	$ 0.01	$ 0.01
Common Stock, Shares, Authorized (shares)	200,000,000	200,000,000
Common Stock, Shares, Issued (shares)	85,529,386	84,253,065
Common Stock, Shares, Outstanding (shares)	85,529,386	84,253,065
6.75% Series C Cumulative Redeemable Perpetual Preferred Stock
Preferred Stock, Par or Stated Value Per Share (usd per share)	$ 0.01	$ 0.01
Preferred Stock, Shares Authorized (shares)	54,461	54,461
Preferred Stock, Shares Issued (shares)	54,458	54,458
Preferred Stock, Shares Outstanding (shares)	54,458	54,458