Capital Stock - Issuances of Common Stock (Details)	6 Months Ended
	Jun. 30, 2016 USD ($) $ / shares shares
Stock Issued During Period, Value, New Issues	$ 6,591,000
At the Market Offering Program [Member]
Value of Common Stock Available to be issued under At The Money Program	$ 8,300,000
At the Market Offering Program [Member] | 2015-Q1 [Member]
Share Price | $ / shares	$ 13.66
Stock Issued During Period Shares New Issues | shares	1,210,487
Stock Issued During Period, Value, New Issues	$ 16,175,000
At the Market Offering Program [Member] | 2015-Q2 [Member]
Share Price | $ / shares	$ 13.65
Stock Issued During Period Shares New Issues | shares	5,024,530
Stock Issued During Period, Value, New Issues	$ 67,100,000
At the Market Offering Program [Member] | 2016-Q2 [Member]
Share Price | $ / shares	$ 10.48
Stock Issued During Period Shares New Issues | shares	646,753
Stock Issued During Period, Value, New Issues	$ 6,591