Background and Business Description Rehabilitation Exit Support Agreement (Details)	6 Months Ended
	Jun. 30, 2017 USD ($)
Gain Contingency, Unrecorded Amount	$ 1,400,000,000
AAC Note Secured by RMBS Securities Value Not Less Than	$ 350,000,000
Amount of Senior Surplus Notes Outstanding on June 8, 2020	25.00%
Rehabilitation Exit Transactions Consummation Period	365 days
Surplus Note Holder Cancellation Percent	66.00%
Deferred Payment Holder Cancellation Percent	66.00%
Cancellation Days Due to No Motion Filed in Rehab Court	75 days
Cancellation Days Due To Non Commencement of Confirmation Hearing	180 days
Cancellation Date Due To Rehab Exit Transactions Not Consummated	270 days
Supporting Holders Cancellation Days Due to Non Consummation	365 days
Condition Precedent Percent of Outstanding Surplus Notes	85.00%
One Time Interest Payment on Surplus Notes	$ 12,500,000
Deferred Payment Obligation [Member]
One Dollar Outstanding	1
Cash Payment Amount	0.40
Payment Amount in New Secured Notes	0.41
Payment Amount in Existing Surplus Notes	0.125
Discount Amount	0.065
Surplus Notes [Member]
One Dollar Outstanding	1
Cash Payment Amount	0.40
Payment Amount in New Secured Notes	0.41
Payment Amount in Existing Surplus Notes	0.125
Discount Amount	$ 0.065
BSA Waiver and Amendment Required Percent	50.00%
Ambac [Member] | Deferred Payment Obligation [Member]
One Dollar Outstanding	$ 1
Payment Amount in New Secured Notes	0.91
Discount Amount	0.09
AFG [Member]
Amount of Remaining Senior Suplus Notes	$ 60,000,000