Stockholders' Equity - Common shares (Details)	0 Months Ended		12 Months Ended
	Jul. 19, 2013	Sep. 28, 2012	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Reconciliation of the beginning and ending common stock outstanding
Issuance of common stock	3,000,000	9,200,000
Balance, end of year			98,828,000	95,924,000
Common Stock [Member]
Reconciliation of the beginning and ending common stock outstanding
Balance, beginning of year			95,924,339	87,514,336	77,843,883
Issuance of common stock			3,073,445	8,293,369	9,275,895
Non-vested stock-based awards, net of withheld shares and forfeitures			(169,686)	116,634	394,558
Balance, end of year			98,828,098	95,924,339	87,514,336