Cash and Marketable Securities	9 Months Ended
Sep. 30, 2020
Cash and Marketable Securities [Abstract]
Cash and Marketable Securities	Note 13. Cash and Marketable Securities Cash, money market funds and certificates of deposit with maturities of three months or less when purchased are included in Cash and cash equivalents in the accompanying condensed consolidated statements of financial position. As of September 30, 2020 and December 31, 2019, marketable securities primarily consisted of treasury bills with maturities of less than one year and are classified as available-for-sale securities. As of September 30, 2020 and December 31, 2019, the amortized cost of our short-term investments was less than $1 million and $7 million, respectively, and the estimated fair value of these investments was less than $1 million and $7 million, respectively. Gains and losses on sales of investments, as determined on a specific identification basis, are included in investment income in the period they are realized. For each of the three and nine months ended September 30, 2020 and 2019, there were no gross realized gains, gross realized losses or proceeds resulting from sales of available-for-sale securities. Maturities of available-for-sale securities were $9 million for each of the nine months ended September 30, 2020 and 2019. We periodically review our portfolio of investments to determine whether an allowance for credit losses is necessary. There was a $3 million loss on an investment recognized in the nine months ended September 30, 2020, which is included in Interest and net investment (income) loss in the accompanying condensed consolidated statements of operations and comprehensive income. There were no credit losses due to declines in the value of our investments recognized for the three months ended September 30, 2020 or the three and nine months ended September 30, 2019.

Cash and Marketable Securities

9 Months Ended

Sep. 30, 2020

Cash and Marketable Securities [Abstract]

Note 13. Cash and Marketable Securities

Cash, money market funds and certificates of deposit with maturities of three months or less when purchased are included in Cash and cash equivalents in the accompanying condensed consolidated statements of financial position. As of September 30, 2020 and December 31, 2019, marketable securities primarily consisted of treasury bills with maturities of less than one year and are classified as available-for-sale securities. As of September 30, 2020 and December 31, 2019, the amortized cost of our short-term investments was less than $1 million and $7 million, respectively, and the estimated fair value of these investments was less than $1 million and $7 million, respectively.

Gains and losses on sales of investments, as determined on a specific identification basis, are included in investment income in the period they are realized. For each of the three and nine months ended September 30, 2020 and 2019, there were no gross realized gains, gross realized losses or proceeds resulting from sales of available-for-sale securities. Maturities of available-for-sale securities were $9 million for each of the nine months ended September 30, 2020 and 2019.

We periodically review our portfolio of investments to determine whether an allowance for credit losses is necessary. There was a $3 million loss on an investment recognized in the nine months ended September 30, 2020, which is included in Interest and net investment (income) loss in the accompanying condensed consolidated statements of operations and comprehensive income. There were no credit losses due to declines in the value of our investments recognized for the three months ended September 30, 2020 or the three and nine months ended September 30, 2019.