Stock Offerings (Details) (USD $)	9 Months Ended		9 Months Ended		3 Months Ended	9 Months Ended	12 Months Ended	0 Months Ended	12 Months Ended		9 Months Ended
	Sep. 30, 2014	Dec. 31, 2013	Sep. 30, 2014 Series B Preferred Stock [Member]	Sep. 30, 2014 Series C Preferred Stock [Member]	Mar. 31, 2014 Common Class A [Member]	Sep. 30, 2014 Common Class A [Member]	Dec. 31, 2013 Common Class A [Member]	Sep. 08, 2011 Preferred Class A [Member]	Dec. 31, 2013 Preferred Class A [Member]	Dec. 31, 2012 Preferred Class A [Member]	Sep. 30, 2014 Preferred Class A [Member] Through 8 March 2016 [Member]	Sep. 30, 2014 Preferred Class A [Member] After 8 March 2016 [Member]
Stock offering
Number of shares issued	9,283	8,500	400	383.4
Dividend rate (as a percent)			6.00%	6.50%					1.00%	1.00%	1.00%	9.00%
Period from first, second, third, fourth, and fifth anniversary of original issue date that stock may be convertible			30 days	30 days
Conversion price (in dollars per share)			$ 16	$ 16
Stock offering (in shares)					2,265,054	361,865	610,194	8,500
Stock offering in process					$ 27,100,000	$ 5,800,000	$ 9,800,000
SBLF capital received	$ 7,834,000							$ 8,500,000
Preferred stock, par value (in dollars per share)	$ 1,000	$ 1,000						$ 1,000