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Summary of Significant Accounting Policies (Investment Securities) (Details)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Accounting Policies [Abstract]
Percentage of investments recorded at fair value	71.00%	87.00%

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- Definition

Represents the percentage of the total investment portfolio recorded at fair value based upon quoted market prices or other observable inputs.

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