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v3.20.4

Marketable Securities (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019
Cash equivalents and marketable securities |  |
Maximum maturity period of available-for-sale securities (in years) | 3 years | 3 years
Fair value | $ 441,186 | $ 363,542
Amortized Cost | 441,244 | 363,587
Gross unrealized gains | 64 | 19
Gross unrealized losses | (122) | (64)
Cash, cash equivalents and marketable securities |  |
Cash, fair value | 61,463 | 44,122
Cash, amortized cost | 61,463 | 44,122
Fair Value | 502,649 | 407,664
Amortized Cost | 502,707 | 407,709
Gross unrealized gains | 64 | 19
Gross unrealized losses | (122) | (64)
Money market funds |  |
Cash equivalents and marketable securities |  |
Fair value | 32,815 | 10,065
Amortized Cost | 32,815 | 10,065
Gross unrealized gains | 0 | 0
Gross unrealized losses | $ 0 | $ 0
Weighted Rate of Return (as a percent) | 0.01% | 1.48%
U.S. Government bonds and notes |  |
Cash equivalents and marketable securities |  |
Fair value | $ 169,880 | $ 39,086
Amortized Cost | 169,920 | 39,087
Gross unrealized gains | 3 | 0
Gross unrealized losses | $ (43) | $ (1)
Weighted Rate of Return (as a percent) | 0.12% | 1.49%
Corporate notes, bonds and commercial paper |  |
Cash equivalents and marketable securities |  |
Fair value | $ 238,491 | $ 314,391
Amortized Cost | 238,509 | 314,435
Gross unrealized gains | 61 | 19
Gross unrealized losses | $ (79) | $ (63)
Weighted Rate of Return (as a percent) | 0.21% | 1.81%

X
- Definition This item represents the weighted rate of return on marketable securities like money market funds, U.S. government bonds and notes, corporate notes, bonds and commercial paper, corporate securities and cash and cash equivalents. + References No definition available. + Details
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Period Type: | instant

X
- Definition This item represents the amortized cost of cash, cash equivalents and marketable securities, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any. + References No definition available. + Details
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- Definition This element represents the aggregate of cash, cash equivalents and marketable securities reported on the balance sheet at period end measured at fair value by the entity. + References No definition available. + Details
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Namespace Prefix: | rmbs_
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- Definition This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the company may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. + References No definition available. + Details
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- Definition This item represents the gross unrealized gains for cash, cash equivalents and marketable securities + References No definition available. + Details
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- Definition This item represents the gross unrealized losses for cash, cash equivalents and marketable securities. + References No definition available. + Details
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- Definition Represents the maximum maturity period of securities invested by the entity. + References No definition available. + Details
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- Definition -- None. No documentation exists for this element. -- + References No definition available. + Details
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- Definition Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading. + References No definition available. + Details
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X
- Definition This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any. + References No definition available. + Details
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- Definition 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. Excludes cash and cash equivalents within disposal group and discontinued operation. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 946 -SubTopic 210 -Section 45 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=118262064&loc=SL116631418-115840 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -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 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 946 -SubTopic 210 -Section 45 -Paragraph 21 -URI http://asc.fasb.org/extlink&oid=118262064&loc=SL116631419-115840 + Details
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