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Investment Securities - Fair Value Measurements (Details)	9 Months Ended	12 Months Ended
	Sep. 30, 2021	Dec. 31, 2020
Investments, Debt and Equity Securities [Abstract]
Percentage of investments recorded at fair value	69.00%	73.00%

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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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No definition available.

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