Regulatory Matters - Capital Ratios for Company and Bank under Federal Regulatory Guidelines (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
SVB Financial Group
CET 1 risk-based capital, Actual Capital Ratios	12.58%	13.41%
CET 1 risk-based capital, Required Capital Ratios	7.00%	6.40%
CET 1 risk-based capital, Actual Capital Amounts	$ 5,857,744	$ 5,167,270
CET 1 risk-based capital, Required Capital Amounts	$ 3,260,424	$ 2,456,151
Tier 1 risk-based capital, Actual Capital Ratios	13.43%	13.58%
Tier 1 risk-based capital, Required Capital Ratios	8.50%	7.90%
Tier 1 risk-based capital, Well Capitalized Capital Ratios	6.00%	6.00%
Tier 1 risk-based capital, Actual Capital Amounts	$ 6,257,442	$ 5,231,476
Tier 1 risk-based capital, Required Capital Amounts	3,959,086	3,034,068
Tier 1 risk-based capital, Well Capitalized Capital Amounts	$ 2,794,649	$ 2,311,671
Total risk-based capital, Actual Capital Ratios	14.23%	14.45%
Total risk-based capital, Required Capital Ratios	10.50%	9.90%
Total risk-based capital, Well Capitalized Capital Ratios	10.00%	10.00%
Total risk-based capital, Actual Capital Amounts	$ 6,630,022	$ 5,567,562
Total risk-based capital, Required Capital Amounts	4,890,636	3,804,625
Total risk-based capital, Well Capitalized Capital Amounts	$ 4,657,748	$ 3,852,785
Tier 1 leverage, Actual Capital Ratios	9.06%	9.06%
Tier 1 leverage, Required Capital Ratios	4.00%	4.00%
Tier 1 leverage, Actual Capital Amounts	$ 6,257,442	$ 5,231,476
Tier 1 leverage, Required Capital Amounts	$ 2,763,146	$ 2,308,592
Silicon Valley Bank
CET 1 risk-based capital, Actual Capital Ratios	11.12%	12.41%
CET 1 risk-based capital, Required Capital Ratios	7.00%	6.40%
CET 1 risk-based capital, Well Capitalized Capital Ratios	6.50%	6.50%
CET 1 risk-based capital, Actual Capital Amounts	$ 4,949,393	$ 4,604,689
CET 1 risk-based capital, Required Capital Amounts	3,115,151	2,365,385
CET 1 risk-based capital, Well Capitalized Capital Amounts	$ 2,892,640	$ 2,411,765
Tier 1 risk-based capital, Actual Capital Ratios	11.12%	12.41%
Tier 1 risk-based capital, Required Capital Ratios	8.50%	7.90%
Tier 1 risk-based capital, Well Capitalized Capital Ratios	8.00%	8.00%
Tier 1 risk-based capital, Actual Capital Amounts	$ 4,949,393	$ 4,604,689
Tier 1 risk-based capital, Required Capital Amounts	3,782,683	2,921,946
Tier 1 risk-based capital, Well Capitalized Capital Amounts	$ 3,560,172	$ 2,968,326
Total risk-based capital, Actual Capital Ratios	11.96%	13.32%
Total risk-based capital, Required Capital Ratios	10.50%	9.90%
Total risk-based capital, Well Capitalized Capital Ratios	10.00%	10.00%
Total risk-based capital, Actual Capital Amounts	$ 5,321,850	$ 4,940,776
Total risk-based capital, Required Capital Amounts	4,672,726	3,664,028
Total risk-based capital, Well Capitalized Capital Amounts	$ 4,450,215	$ 3,710,408
Tier 1 leverage, Actual Capital Ratios	7.30%	8.10%
Tier 1 leverage, Required Capital Ratios	4.00%	4.00%
Tier 1 leverage, Well Capitalized Capital Ratios	5.00%	5.00%
Tier 1 leverage, Actual Capital Amounts	$ 4,949,393	$ 4,604,689
Tier 1 leverage, Required Capital Amounts	2,713,367	2,272,912
Tier 1 leverage, Well Capitalized Capital Amounts	$ 3,391,709	$ 2,841,139

Common Equity Tier One Capital Required For Capital Adequacy To Risk Weighted Assets

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Common Equity Tier One Capital Required To Be Well Capitalized To Risk Weighted Assets

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The amount of total capital as defined in the regulations.

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The minimum amount of Total Capital required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The minimum Total risk based capital ratio (total capital divided by risk weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The amount of Total Capital required to be categorized as well as capitalized under the regulatory framework for prompt corrective action.

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The Total risk based capital ratio (total capital divided by risk weighted assets) required to be categorized as "well capitalized", in the regulatory framework for prompt corrective action.

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Total Capital divided by risk weighted assets as defined in the regulations.

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Amount of Common Equity Tier One Risk-based Capital, as defined by regulatory framework.

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Percentage of Common Equity Tier One Risk-based Capital to total risk-weighted assets, as defined by regulatory framework.

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Amount of Common Equity Tier 1 Risk-based Capital required to be categorized as adequately capitalized under regulatory framework for prompt corrective action.

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Tier 1 Leverage Capital as defined in the regulations. Also called Core Capital.

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The minimum amount of Tier 1 Leverage Capital required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The amount of Tier 1 Leverage Capital required to be categorized as well capitalized under the regulatory framework for prompt corrective action.

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Tier 1 Leverage Capital divided by average assets as defined in the regulations.

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Tier 1 Risk Based Capital as defined in the regulations.

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Tier 1 capital divided by risk weighted assets as defined by regulations.

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