Financing Instruments - Note Purchase Agreements - Guaranty Agreement (Details) - USD ($) $ / shares in Units, $ in Millions	Dec. 10, 2013	Dec. 31, 2016	Dec. 31, 2015
Line of Credit Facility [Line Items]
Common stock shares outstanding		123,494,129	122,125,072
Note Purchase Agreement [Member]
Line of Credit Facility [Line Items]
Stock issued during the period (shares)	3,700,000
Restricted common stock par value (in USD per share)	$ 0.01
Stock closing price (in USD per share)	$ 0.60
Stock issued during the period, value	$ 2.2
Common stock shares outstanding		3,681,000	2,523,347
Common stock outstanding, value		$ 2.2	$ 1.5