XML 64 R52.htm IDEA: XBRL DOCUMENT
v3.23.1

FAIR VALUE OF FINANCIAL INSTRUMENTS - Cumulative unrealized gains and losses (Details) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Cumulative unrealized gains and losses from Investments in debt and equity securities |  |  |
Cost | $ 24,800,998 | $ 10,747,733 |
Gross Unrealized Gains | 4,856,316 | 2,521,253 |
Aggregate Fair Value | 29,657,314 | 13,268,986 |
Unrealized gains on investments in debt and equity securities | 2,343,359 | 513,529 | $ 1,870,010
Equity securities |  |  |
Cumulative unrealized gains and losses from Investments in debt and equity securities |  |  |
Cost | 22,913,739 | 6,729,245 |
Gross Unrealized Gains | 4,778,720 | 2,383,362 |
Aggregate Fair Value | 27,692,459 | 9,112,607 |
Mutual funds |  |  |
Cumulative unrealized gains and losses from Investments in debt and equity securities |  |  |
Cost | 1,252,804 |  |
Gross Unrealized Gains | 50,169 |  |
Aggregate Fair Value | 1,302,973 |  |
Mutual funds and exchange traded funds |  |  |
Cumulative unrealized gains and losses from Investments in debt and equity securities |  |  |
Cost |  | 4,018,488 |
Gross Unrealized Gains |  | 137,891 |
Aggregate Fair Value |  | $ 4,156,379 |
Municipal bonds |  |  |
Cumulative unrealized gains and losses from Investments in debt and equity securities |  |  |
Cost | 634,455 |  |
Gross Unrealized Gains | 27,427 |  |
Aggregate Fair Value | $ 661,882 |  |

X
- Definition Amount of accumulated gross unrealized gain on investments in debt securities, trading and equity securities measured at fair value. + References No definition available. + Details
Name: | rvp_DebtSecuritiesTradingAndEquitySecuritiesAccumulatedGrossUnrealizedGain
Namespace Prefix: | rvp_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of unrealized gain (loss) on investment in debt and equity securities. + References No definition available. + Details
Name: | us-gaap_DebtAndEquitySecuritiesUnrealizedGainLoss
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Cost of investment in debt investment in debt security measured at fair value with change in fair value recognized in net income (trading) and investment in equity security with change in fair value recognized in net income (FV-NI). Excludes equity method investment and investment in equity security without readily determinable fair value. + References No definition available. + Details
Name: | us-gaap_DebtSecuritiesTradingAndEquitySecuritiesFvNiCost
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- References No definition available. + Details
Name: | us-gaap_DebtSecuritiesTradingAndEquitySecuritiesFvNiCostAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading) and investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.4) -URI https://asc.fasb.org/extlink&oid=126897435&loc=d3e534808-122878 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section 45 -Paragraph 1 -Subparagraph (f) -URI https://asc.fasb.org/extlink&oid=124098289&loc=d3e6676-107765 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(2)) -URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
Name: | us-gaap_TradingSecurities
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_InvestmentTypeAxis=us-gaap_EquitySecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_InvestmentTypeAxis=us-gaap_MutualFundMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_InvestmentTypeAxis=rvp_MutualFundsAndExchangeTradedFundsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_InvestmentTypeAxis=us-gaap_MunicipalBondsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |