Business Segments - Segment Debt (Details)	9 Months Ended
Sep. 30, 2018
Mortgage Banking \| FHLB Advances
Business Segments
Variable rate, spread (as a percent)	0.50%
Consumer Finance \| Minimum
Business Segments
Variable rate, spread (as a percent)	2.00%
Consumer Finance \| Maximum
Business Segments
Variable rate, spread (as a percent)	8.00%
Consumer Finance \| LIBOR \| Minimum
Business Segments
Variable rate, spread (as a percent)	2.00%

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No definition available.

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