Statements of Cash Flows (Parenthetical) - USD ($)	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Components of Cash and Cash Equivalents:
Cash and Cash Equivalents	$ 1,223,159,803	$ 1,846,630,713	$ 2,920,517,807
Equity in Trading Accounts:
Cash and Cash Equivalents	433,776,173	144,626,242	249,864,944
Total Cash, Cash Equivalents and Equity in Trading Accounts	$ 1,656,935,976	$ 1,991,256,955	$ 3,170,382,751

Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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