Fair Value of Financial Instruments - Summary of Estimated Fair Values of Investments and Remaining Unfunded Commitments for Each Major Category of Investments (Textual) (Detail) $ in Thousands	9 Months Ended
Sep. 30, 2016 USD ($)
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Fair Value	$ 495,447
Unfunded Commitments	22,455
Non-marketable securities \| Fair value accounting \| Venture capital and private equity fund investments
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Fair Value	141,841
Unfunded Commitments	$ 5,309
Non-marketable securities \| Fair value accounting \| Venture capital and private equity fund investments \| Lower Limit
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Period distributions from fund investments to be received	10 years
Non-marketable securities \| Fair value accounting \| Venture capital and private equity fund investments \| Upper Limit
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Period distributions from fund investments to be received	13 years
Non-marketable securities \| Fair value accounting \| Venture capital and private equity fund investments \| Noncontrolling Interests
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Fair Value	$ 101,000
Unfunded Commitments	4,000
Non-marketable securities \| Equity method accounting \| Venture capital and private equity fund investments
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Fair Value	84,904
Unfunded Commitments	$ 4,954
Non-marketable securities \| Equity method accounting \| Venture capital and private equity fund investments \| Lower Limit
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Period distributions from fund investments to be received	10 years
Non-marketable securities \| Equity method accounting \| Venture capital and private equity fund investments \| Upper Limit
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Period distributions from fund investments to be received	13 years

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

+ Details

Name:	us-gaap_FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Estimate remaining period the underlying assets are expected to be liquidated by the investees for investments for which net asset value per share is calculated (including by unit, membership interest, or other ownership interest unit measure), in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 6A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=36462937&loc=SL6742756-110258

+ Details

Name:	us-gaap_FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareLiquidatingInvestmentRemainingPeriod1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

The total fair value for all investments, comprising or included in the major category, of those certain investments for which net asset value per share is calculated (including by unit, membership interest, or other equity (ownership interest) unit measure) (alternative investments) for which the entity has intentions to sell or liquidate, but the specific assets for sale or liquidation have not been identified (for example, the entity intends to sell $10,000,000 of its investments in private equity funds, but the individual investments to be sold have not been identified).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 6A
-Subparagraph (h)
-URI http://asc.fasb.org/extlink&oid=36462937&loc=SL6742756-110258

+ Details

Name:	us-gaap_FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerSharePlannedSaleInvestmentsNotIdentifiedValue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The amount of unfunded commitments for which the entity is obligated, to those certain investments for which net asset value per share is calculated (including by unit, membership interest, or other equity (ownership interest) unit measure) (alternative investments).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 6A
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=36462937&loc=SL6742756-110258

+ Details

Name:	us-gaap_FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareUnfundedCommittments
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

Name:	invest_InvestmentAxis=sivb_NonmarketableSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_InvestmentTypeAxis=sivb_FairValueAccountingMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	sivb_InvestmentHoldingsAxis=sivb_VentureCapitalAndPrivateEquityFundInvestmentsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=us-gaap_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=us-gaap_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementEquityComponentsAxis=us-gaap_NoncontrollingInterestMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_InvestmentTypeAxis=us-gaap_EquityMethodInvestmentsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: