At-the-Market (ATM) Program (Details) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
	Sep. 30, 2015	Dec. 31, 2015
Proceeds from At-the-Market (ATM) program		$ 36,348
ATM
Shares authorized	12,000,000
Shares issued pursuant to at-the-market program, net (in shares)		714,301
Proceeds from At-the-Market (ATM) program		$ 36,300