CASH EQUIVALENTS.	12 Months Ended
Dec. 31, 2020
Cash and Cash Equivalents [Abstract]
CASH EQUIVALENTS	CASH EQUIVALENTS.Cash equivalent investments in the T. Rowe Price money market mutual funds aggregate to $1,931.1 million at December 31, 2020, and $1,355.6 million at December 31, 2019. Dividends earned on these investments totaled $4.2 million in 2020, $33.3 million in 2019, and $27.0 million in 2018.

The entire disclosure for cash and cash equivalent footnotes, which may include the types of deposits and money market instruments, applicable carrying amounts, restricted amounts and compensating balance arrangements. Cash and equivalents include: (1) currency on hand (2) demand deposits with banks or financial institutions (3) other kinds of accounts that have the general characteristics of demand deposits (4) 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. Generally, only investments maturing within three months from the date of acquisition qualify.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(1))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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