Columbia Funds Variable Series Trust II N-CSRS 5 Sep 24 Certified semi-annual shareholder report (management investment company) Financial data

Form N-CSR Cover

Form N-CSR Cover	6 Months Ended
	Jun. 30, 2024
Shareholder Report [Line Items]
Document Type	N-CSRS
Amendment Flag	false
Registrant Name	Columbia Funds Variable Series Trust II
Entity Central Index Key	0001413032
Entity Investment Company Type	N-1A
Document Period End Date	Jun. 30, 2024

Shareholder Report

Shareholder Report	6 Months Ended
	Jun. 30, 2024 USD ($) Holding
Shareholder Report [Line Items]
Document Type	N-CSRS
Amendment Flag	false
Registrant Name	Columbia Funds Variable Series Trust II
Entity Central Index Key	0001413032
Entity Investment Company Type	N-1A
Document Period End Date	Jun. 30, 2024
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 1
Shareholder Report [Line Items]
Fund Name	Columbia Variable Portfolio – U.S. Government Mortgage Fund
Class Name	Class 1
No Trading Symbol Flag	true
Annual or Semi-Annual Statement [Text Block]	This semiannual shareholder report
Shareholder Report Annual or Semi-Annual	semi - annual shareholder report
Additional Information [Text Block]	You can find additional information about the Fund at columbiathreadneedleus.com/resources/literature 1-800-345-6611.
Additional Information Phone Number	1-800-345-6611
Additional Information Website	columbiathreadneedleus.com/resources/literature
Expenses [Text Block]	What were the Fund costs for the reporting period? (Based on a hypothetical $10,000 investment) Class Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Class 1 $ 0.46 %
Expenses Paid, Amount	$ 23
Expense Ratio, Percent	0.46%
Net Assets	$ 869,779,107
Holdings Count | Holding	299
Investment Company, Portfolio Turnover	151%
Additional Fund Statistics [Text Block]	Key Fund Statistics Fund net assets $ Total number of portfolio holdings 299 Portfolio turnover for the reporting period 151%
Holdings [Text Block]	Graphical Representation of Fund The tables below show the investment makeup of the Fund represented as a percentage of Fund net assets. Derivatives are excluded Bond ratings on Fund holdings are divided into Top Holdings Uniform Mortgage-Backed Security TBA 5.9 % Government National Mortgage Association TBA 4.4 % Uniform Mortgage-Backed Security TBA 3.6 % Uniform Mortgage-Backed Security TBA 2.9 % Uniform Mortgage-Backed Security TBA 2.7 % Uniform Mortgage-Backed Security TBA 2.5 % Federal National Mortgage Association 2.5 % Uniform Mortgage-Backed Security TBA 2.3 % Federal National Mortgage Association 2.1 % Federal National Mortgage Association 1.9 % Asset Categories Credit Quality
Credit Quality Explanation [Text Block]	Bond ratings on Fund holdings are divided into
Largest Holdings [Text Block]	Top Holdings Uniform Mortgage-Backed Security TBA 5.9 % Government National Mortgage Association TBA 4.4 % Uniform Mortgage-Backed Security TBA 3.6 % Uniform Mortgage-Backed Security TBA 2.9 % Uniform Mortgage-Backed Security TBA 2.7 % Uniform Mortgage-Backed Security TBA 2.5 % Federal National Mortgage Association 2.5 % Uniform Mortgage-Backed Security TBA 2.3 % Federal National Mortgage Association 2.1 % Federal National Mortgage Association 1.9 %
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 2
Shareholder Report [Line Items]
Fund Name	Columbia Variable Portfolio – U.S. Government Mortgage Fund
Class Name	Class 2
No Trading Symbol Flag	true
Annual or Semi-Annual Statement [Text Block]	This semiannual shareholder report
Shareholder Report Annual or Semi-Annual	semi - annual shareholder report
Additional Information [Text Block]	You can find additional information about the Fund at columbiathreadneedleus.com/resources/literature 1-800-345-6611.
Additional Information Phone Number	1-800-345-6611
Additional Information Website	columbiathreadneedleus.com/resources/literature
Expenses [Text Block]	What were the Fund costs for the reporting period? (Based on a hypothetical $10,000 investment) Class Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Class 2 $ 0.71 %
Expenses Paid, Amount	$ 35
Expense Ratio, Percent	0.71%
Net Assets	$ 869,779,107
Holdings Count | Holding	299
Investment Company, Portfolio Turnover	151%
Additional Fund Statistics [Text Block]	Key Fund Statistics Fund net assets $ Total number of portfolio holdings 299 Portfolio turnover for the reporting period 151%
Holdings [Text Block]	Graphical Representation of Fund The tables below show the investment makeup of the Fund represented as a percentage of Fund net assets. Derivatives are excluded from the tables unless otherwise noted. The Fund's portfolio composition is subject to change. Bond ratings on Fund holdings are divided into categories ranging from highest to lowest credit quality, determined by using the middle rating of Moody’s, S&P and Fitch, after dropping the highest and lowest available ratings. When ratings are available from only two rating agencies, the lower rating is used. When a rating is available from only one rating agency, that rating is used. If a security is not rated by Moody's, S&P and Fitch, but has a rating by Kroll and/or DBRS, the same methodology is applied to those bonds that would otherwise be not rated. When a bond is not rated by any rating agency, it is designated as “Not rated.” Credit quality ratings assigned by a rating agency are subjective opinions, not statements of fact, and are subject to change, including daily. Top Holdings Uniform Mortgage-Backed Security TBA 5.9% Government National Mortgage Association TBA 4.4% Uniform Mortgage-Backed Security TBA 3.6% Uniform Mortgage-Backed Security TBA 2.9% Uniform Mortgage-Backed Security TBA 2.7% Uniform Mortgage-Backed Security TBA 2.5% Federal National Mortgage Association 2.5% Uniform Mortgage-Backed Security TBA 2.3% Federal National Mortgage Association 2.1% Federal National Mortgage Association 1.9% Asset Categories Credit Quality
Credit Quality Explanation [Text Block]	Bond ratings on Fund holdings are divided into categories ranging from highest to lowest credit quality, determined by using the middle rating of Moody’s, S&P and Fitch, after dropping the highest and lowest available ratings. When ratings are available from only two rating agencies, the lower rating is used. When a rating is available from only one rating agency, that rating is used. If a security is not rated by Moody's, S&P and Fitch, but has a rating by Kroll and/or DBRS, the same methodology is applied to those bonds that would otherwise be not rated. When a bond is not rated by any rating agency, it is designated as “Not rated.” Credit quality ratings assigned by a rating agency are subjective opinions, not statements of fact, and are subject to change, including daily.
Largest Holdings [Text Block]	Top Holdings Uniform Mortgage-Backed Security TBA 5.9% Government National Mortgage Association TBA 4.4% Uniform Mortgage-Backed Security TBA 3.6% Uniform Mortgage-Backed Security TBA 2.9% Uniform Mortgage-Backed Security TBA 2.7% Uniform Mortgage-Backed Security TBA 2.5% Federal National Mortgage Association 2.5% Uniform Mortgage-Backed Security TBA 2.3% Federal National Mortgage Association 2.1% Federal National Mortgage Association 1.9%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 3
Shareholder Report [Line Items]
Fund Name	Columbia Variable Portfolio – U.S. Government Mortgage Fund
Class Name	Class 3
No Trading Symbol Flag	true
Annual or Semi-Annual Statement [Text Block]	This semiannual shareholder report
Shareholder Report Annual or Semi-Annual	semi - annual shareholder report
Additional Information [Text Block]	You can find additional information about the Fund at columbiathreadneedleus.com/resources/literature 1-800-345-6611.
Additional Information Phone Number	1-800-345-6611
Additional Information Website	columbiathreadneedleus.com/resources/literature
Expenses [Text Block]	What were the Fund costs for the reporting period (Based on a hypothetical $10,000 investment) Class Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Class 3 $ 0.58 %
Expenses Paid, Amount	$ 29
Expense Ratio, Percent	0.58%
Net Assets	$ 869,779,107
Holdings Count | Holding	299
Investment Company, Portfolio Turnover	151%
Additional Fund Statistics [Text Block]	Key Fund Statistics Fund net assets $ Total number of portfolio holdings 299 Portfolio turnover for the reporting period 151%
Holdings [Text Block]	Graphical Representation of Fund The tables below show the investment makeup of the Fund represented as a percentage of Fund net assets. Derivatives are excluded from the tables unless otherwise noted. The Fund's portfolio composition is subject to change. Bond ratings on Fund holdings are divided into categories ranging from highest to lowest credit quality, determined by using the middle rating of has Top Holdings Uniform Mortgage-Backed Security TBA 5.9% Government National Mortgage Association TBA 4.4% Uniform Mortgage-Backed Security TBA 3.6% Uniform Mortgage-Backed Security TBA 2.9% Uniform Mortgage-Backed Security TBA 2.7% Uniform Mortgage-Backed Security TBA 2.5% Federal National Mortgage Association 2.5% Uniform Mortgage-Backed Security TBA 2.3% Federal National Mortgage Association 2.1% Federal National Mortgage Association 1.9% Asset Categories Credit Quality
Credit Quality Explanation [Text Block]	Bond ratings on Fund holdings are divided into categories ranging from highest to lowest credit quality, determined by using the middle rating of has
Largest Holdings [Text Block]	Top Holdings Uniform Mortgage-Backed Security TBA 5.9% Government National Mortgage Association TBA 4.4% Uniform Mortgage-Backed Security TBA 3.6% Uniform Mortgage-Backed Security TBA 2.9% Uniform Mortgage-Backed Security TBA 2.7% Uniform Mortgage-Backed Security TBA 2.5% Federal National Mortgage Association 2.5% Uniform Mortgage-Backed Security TBA 2.3% Federal National Mortgage Association 2.1% Federal National Mortgage Association 1.9%

Shareholder Report, Holdings (D

Shareholder Report, Holdings (Details)	Jun. 30, 2024
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 3 | Uniform MortgageBacked Security TBA 07152054 3.500 [Member]
Holdings [Line Items]
Percent of Net Asset Value	5.90%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 3 | Government National Mortgage Association TBA 07222054 4.500 [Member]
Holdings [Line Items]
Percent of Net Asset Value	4.40%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 3 | Uniform MortgageBacked Security TBA 07152054 5.000 [Member]
Holdings [Line Items]
Percent of Net Asset Value	3.60%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 3 | Uniform MortgageBacked Security TBA 07152054 6.000 [Member]
Holdings [Line Items]
Percent of Net Asset Value	2.90%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 3 | Uniform MortgageBacked Security TBA 07152054 4.000 [Member]
Holdings [Line Items]
Percent of Net Asset Value	2.70%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 3 | Uniform MortgageBacked Security TBA 07152054 4.500 [Member]
Holdings [Line Items]
Percent of Net Asset Value	2.50%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 3 | Federal National Mortgage Association 03252028 3.129 [Member]
Holdings [Line Items]
Percent of Net Asset Value	2.50%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 3 | Uniform MortgageBacked Security TBA 07152054 2.000 [Member]
Holdings [Line Items]
Percent of Net Asset Value	2.30%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 3 | Federal National Mortgage Association 12012050 2.000 [Member]
Holdings [Line Items]
Percent of Net Asset Value	2.10%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 3 | Federal National Mortgage Association 08012052 4.000 [Member]
Holdings [Line Items]
Percent of Net Asset Value	1.90%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 3 | Fitch, AA Rating [Member]
Holdings [Line Items]
Percent of Net Asset Value	116.20%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 3 | Fitch, A Rating [Member]
Holdings [Line Items]
Percent of Net Asset Value	3.60%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 3 | Fitch, BBB Rating [Member]
Holdings [Line Items]
Percent of Net Asset Value	1.50%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 3 | Fitch, BB Rating [Member]
Holdings [Line Items]
Percent of Net Asset Value	0.40%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 3 | Fitch, B Rating [Member]
Holdings [Line Items]
Percent of Net Asset Value	0.40%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 3 | Not rated [Member]
Holdings [Line Items]
Percent of Net Asset Value	0.90%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 3 | Residential Mortgage Backed Securities Agency [Member]
Holdings [Line Items]
Percent of Net Asset Value	106.60%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 3 | Asset Backed Securities Non Agency [Member]
Holdings [Line Items]
Percent of Net Asset Value	5.80%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 3 | Money Market Fund [Member]
Holdings [Line Items]
Percent of Net Asset Value	4.50%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 3 | Residential Mortgage Backed Securities Non Agency [Member]
Holdings [Line Items]
Percent of Net Asset Value	4.10%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 3 | Commercial Mortgage Backed Securities Agency [Member]
Holdings [Line Items]
Percent of Net Asset Value	3.30%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 3 | Commercial Mortgage Backed Securities Non Agency [Member]
Holdings [Line Items]
Percent of Net Asset Value	3.10%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 3 | Other [Member]
Holdings [Line Items]
Percent of Net Asset Value	0.10%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 2 | Uniform MortgageBacked Security TBA 07152054 3.500 [Member]
Holdings [Line Items]
Percent of Net Asset Value	5.90%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 2 | Government National Mortgage Association TBA 07222054 4.500 [Member]
Holdings [Line Items]
Percent of Net Asset Value	4.40%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 2 | Uniform MortgageBacked Security TBA 07152054 5.000 [Member]
Holdings [Line Items]
Percent of Net Asset Value	3.60%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 2 | Uniform MortgageBacked Security TBA 07152054 6.000 [Member]
Holdings [Line Items]
Percent of Net Asset Value	2.90%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 2 | Uniform MortgageBacked Security TBA 07152054 4.000 [Member]
Holdings [Line Items]
Percent of Net Asset Value	2.70%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 2 | Uniform MortgageBacked Security TBA 07152054 4.500 [Member]
Holdings [Line Items]
Percent of Net Asset Value	2.50%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 2 | Federal National Mortgage Association 03252028 3.129 [Member]
Holdings [Line Items]
Percent of Net Asset Value	2.50%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 2 | Uniform MortgageBacked Security TBA 07152054 2.000 [Member]
Holdings [Line Items]
Percent of Net Asset Value	2.30%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 2 | Federal National Mortgage Association 12012050 2.000 [Member]
Holdings [Line Items]
Percent of Net Asset Value	2.10%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 2 | Federal National Mortgage Association 08012052 4.000 [Member]
Holdings [Line Items]
Percent of Net Asset Value	1.90%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 2 | Fitch, AA Rating [Member]
Holdings [Line Items]
Percent of Net Asset Value	116.20%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 2 | Fitch, A Rating [Member]
Holdings [Line Items]
Percent of Net Asset Value	3.60%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 2 | Fitch, BBB Rating [Member]
Holdings [Line Items]
Percent of Net Asset Value	1.50%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 2 | Fitch, BB Rating [Member]
Holdings [Line Items]
Percent of Net Asset Value	0.40%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 2 | Fitch, B Rating [Member]
Holdings [Line Items]
Percent of Net Asset Value	0.40%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 2 | Not rated [Member]
Holdings [Line Items]
Percent of Net Asset Value	0.90%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 2 | Residential Mortgage Backed Securities Agency [Member]
Holdings [Line Items]
Percent of Net Asset Value	106.60%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 2 | Asset Backed Securities Non Agency [Member]
Holdings [Line Items]
Percent of Net Asset Value	5.80%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 2 | Money Market Fund [Member]
Holdings [Line Items]
Percent of Net Asset Value	4.50%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 2 | Residential Mortgage Backed Securities Non Agency [Member]
Holdings [Line Items]
Percent of Net Asset Value	4.10%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 2 | Commercial Mortgage Backed Securities Agency [Member]
Holdings [Line Items]
Percent of Net Asset Value	3.30%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 2 | Commercial Mortgage Backed Securities Non Agency [Member]
Holdings [Line Items]
Percent of Net Asset Value	3.10%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 2 | Other [Member]
Holdings [Line Items]
Percent of Net Asset Value	0.10%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 1 | Uniform MortgageBacked Security TBA 07152054 3.500 [Member]
Holdings [Line Items]
Percent of Net Asset Value	5.90%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 1 | Government National Mortgage Association TBA 07222054 4.500 [Member]
Holdings [Line Items]
Percent of Net Asset Value	4.40%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 1 | Uniform MortgageBacked Security TBA 07152054 5.000 [Member]
Holdings [Line Items]
Percent of Net Asset Value	3.60%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 1 | Uniform MortgageBacked Security TBA 07152054 6.000 [Member]
Holdings [Line Items]
Percent of Net Asset Value	2.90%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 1 | Uniform MortgageBacked Security TBA 07152054 4.000 [Member]
Holdings [Line Items]
Percent of Net Asset Value	2.70%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 1 | Uniform MortgageBacked Security TBA 07152054 4.500 [Member]
Holdings [Line Items]
Percent of Net Asset Value	2.50%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 1 | Federal National Mortgage Association 03252028 3.129 [Member]
Holdings [Line Items]
Percent of Net Asset Value	2.50%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 1 | Uniform MortgageBacked Security TBA 07152054 2.000 [Member]
Holdings [Line Items]
Percent of Net Asset Value	2.30%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 1 | Federal National Mortgage Association 12012050 2.000 [Member]
Holdings [Line Items]
Percent of Net Asset Value	2.10%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 1 | Federal National Mortgage Association 08012052 4.000 [Member]
Holdings [Line Items]
Percent of Net Asset Value	1.90%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 1 | Fitch, AA Rating [Member]
Holdings [Line Items]
Percent of Net Asset Value	116.20%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 1 | Fitch, A Rating [Member]
Holdings [Line Items]
Percent of Net Asset Value	3.60%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 1 | Fitch, BBB Rating [Member]
Holdings [Line Items]
Percent of Net Asset Value	1.50%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 1 | Fitch, BB Rating [Member]
Holdings [Line Items]
Percent of Net Asset Value	0.40%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 1 | Fitch, B Rating [Member]
Holdings [Line Items]
Percent of Net Asset Value	0.40%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 1 | Not rated [Member]
Holdings [Line Items]
Percent of Net Asset Value	0.90%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 1 | Residential Mortgage Backed Securities Agency [Member]
Holdings [Line Items]
Percent of Net Asset Value	106.60%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 1 | Asset Backed Securities Non Agency [Member]
Holdings [Line Items]
Percent of Net Asset Value	5.80%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 1 | Money Market Fund [Member]
Holdings [Line Items]
Percent of Net Asset Value	4.50%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 1 | Residential Mortgage Backed Securities Non Agency [Member]
Holdings [Line Items]
Percent of Net Asset Value	4.10%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 1 | Commercial Mortgage Backed Securities Agency [Member]
Holdings [Line Items]
Percent of Net Asset Value	3.30%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 1 | Commercial Mortgage Backed Securities Non Agency [Member]
Holdings [Line Items]
Percent of Net Asset Value	3.10%
Columbia Variable Portfolio – U.S. Government Mortgage Fund Class 1 | Other [Member]
Holdings [Line Items]
Percent of Net Asset Value	0.10%