Regulatory Matters and Significant Risks or Uncertainties - Dividend and Interest Restrictions (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Mar. 31, 2016	Jun. 30, 2014	Jun. 30, 2016	Dec. 31, 2015
Class of Stock [Line Items]
Preferred stock, shares outstanding (in shares)			14,856	18,856
Stock Repurchased and Retired During Period, Shares	4,000	11,551	4,000
Series A Preferred Stock [Member]
Class of Stock [Line Items]
Preferred stock dividend in arrears			$ 8.1