Investing Receivables (Tables)  | 
9 Months Ended | ||||||||||||||||||||||||||||||||||||||||||||||||
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Sep. 30, 2018  | |||||||||||||||||||||||||||||||||||||||||||||||||
| Receivables [Abstract] | |||||||||||||||||||||||||||||||||||||||||||||||||
| Schedule of investing receivables | 
 Investing receivables, including accrued interest thereon, consisted of the following (in thousands): 
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| X | ||||||||||
- Definition Tabular disclosure of the carrying amounts of mortgage and other investing receivables, by major class. No definition available. 
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| X | ||||||||||
- References No definition available. 
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