Basis of Presentation (Policies)	6 Months Ended
Basis of Presentation (Policies)	Jun. 30, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Principles of Consolidation and Presentation	Principles of Consolidation and Presentation Prior to April 1, 2015, the Company’s consolidated financial statements included the accounts of SVB Financial Group and entities in which we had a controlling interest. The determination of whether we had controlling interest was based on consolidation principles prescribed by ASC Topic 810 and whether the controlling interest in an entity was a voting interest entity or a variable interest entity (“VIE”). However, during the three months ended June 30, 2015, we early adopted the provisions of ASU 2015-02, Amendments to the Consolidation Analysis (ASU 2015-02)(see "Adoption of New Accounting Standards" below), which simplifies consolidation accounting by reducing the number of consolidation models and changing various aspects of current GAAP, including certain consolidation criteria for variable interest entities. The new guidance eliminates the presumption that a general partner of a limited partnership arrangement should consolidate a limited partnership. The amendments to ASC Topic 810 in ASU 2015-02 modify the evaluation of whether limited partnerships and similar entities are VIEs or voting entities. With these changes, we determined that the majority of our investments in limited partnership arrangements are VIEs under the new guidance while these entities were typically voting interest entities under the prior guidance. ASU 2015-02 provided a single model for evaluating VIE entities for consolidation. VIEs are entities where investors lack sufficient equity at risk for the entity to finance its activities without additional subordinated financial support or equity investors, as a group, lack one of the following characteristics: (a) the power to direct the activities that most significantly impact the entity’s economic performance, (b) the obligation to absorb the expected losses of the entity, or (c) the right to receive the expected returns of the entity. We assess VIEs to determine if we are the primary beneficiary of a VIE. A primary beneficiary is defined as a variable interest holder that has a controlling financial interest. A controlling financial interest requires both: (a) power to direct the activities that most significantly impact the VIE’s economic performance, and (b) obligation to absorb losses or receive benefits of a VIE that could potentially be significant to a VIE. Under this analysis, we evaluate kick-out rights and other participating rights which could provide us a controlling financial interest. The primary beneficiary of a VIE is required to consolidate the VIE. ASU 2015-02 also changed how we evaluate fees paid to managers of our limited partnership investments. Under the new guidance, we exclude those fee arrangements that are not deemed to be variable interests from the analysis of our interests in our investments in VIEs and the determination of a primary beneficiary, if any. Our consolidated financial statements include the accounts of SVB Financial Group and consolidated entities. We consolidate voting entities in which we have control through voting interests. We determine whether we have a controlling financial interest in a VIE by determining if we have the power to direct the activities of the VIE that most significantly impact the entity’s economic performance and whether we have significant variable interests. Generally, we have significant variable interests if our commitments to a limited partnership investment represent a significant amount of the total commitments to the entity. We also evaluate the impact of related parties on our determination of variable interests in our consolidation conclusions. We consolidate VIEs in which we are the primary beneficiary based on a controlling financial interest. If we are not the primary beneficiary of a VIE, we record our pro-rata interests or our cost basis in the VIE, as appropriate, based on other accounting guidance within GAAP. All significant intercompany accounts and transactions with consolidated entities have been eliminated. We have not provided financial or other support during the periods presented to any VIE that we were not previously contractually required to provide.
Adoption Accounting Pronouncements	Adoption of New Accounting Standards In February 2015, the FASB issued a new accounting standard, ASU 2015-02, which amends the consolidation requirement for certain legal entities. As outlined above in "Principles of Consolidation and Presentation", we early adopted this guidance in the second quarter of 2015 using the modified retrospective method, which results in an effective date of adoption of January 1, 2015 and will not require the restatement of prior period results. The adoption of this guidance impacted our statement of financial position and results of operations, but had no impact on retained earnings, SVBFG stockholders' equity or net income as investments that were consolidated in previous reporting periods are now deconsolidated and no new investments were consolidated. Refer to Note 4—”Variable Interest Entities” of the “Notes to Interim Consolidated Financial Statements (unaudited)” under Part I, Item 1 of this report for additional details regarding our assessment of the adoption of this guidance. In May 2015, the FASB issued a new accounting standard (ASU 2015-07, Fair Value Measurement (Topic 820)), which removes the requirement to categorize within the fair value hierarchy all investments for which fair value is measured using the net asset value per share practical expedient. The standard is required to be applied retrospectively to all periods presented. The guidance will be effective for fiscal years beginning after December 15, 2015, with early adoption permitted. We early adopted this guidance in the second quarter of 2015. The adoption of this guidance impacts our fair value disclosures and has no impact on our financial position, results of operations or stockholders' equity. In January 2014, the FASB issued a new accounting standard (ASU 2014-01, Investments - Equity Method and Joint Ventures (Topic 323), Accounting for Investments in Qualified Affordable Housing Projects), which is effective for us for interim and annual reporting periods beginning after December 15, 2014. The standard is required to be applied retrospectively, with an adjustment to retained earnings in the earliest period presented. The ASU is applicable to our portfolio of low income housing tax credit ("LIHTC") partnership interests. We adopted this guidance in the first quarter of 2015. For prior periods, pursuant to ASU 2014-01, (i) amortization expense related to our low income housing tax credits was reclassified from Other noninterest expense to Income tax expense, (ii) additional amortization, net of the associated tax benefits, was recognized in Income tax expense as a result of our adoption of the proportional amortization method and (iii) net deferred tax assets, related to our low income housing tax investments, were written-off. The cumulative effect to retained earnings as of January 1, 2015 of adopting this guidance was a reduction of $4.7 million, inclusive of a $4.6 million reduction to retained earnings as of January 1, 2014. Our previously reported net income and diluted earnings per share for the three and six months ending June 30, 2014 were not materially impacted by the adoption of ASU 2014-01. Recent Accounting Pronouncements In May 2014, the FASB issued a new accounting standard (ASU 2014-09, Revenue from Contracts with Customers (Topic 606)), which provides revenue recognition guidance that is intended to create greater consistency with respect to how and when revenue from contracts with customers is shown in the income statement. This guidance will be effective on a retrospective basis beginning on January 1, 2018. We do not expect the adoption of this guidance to have a material impact on our financial position, results of operations or stockholders' equity. In August 2014, the FASB issued a new accounting standard (ASU 2014-15, Going Concern (Topic 205-40)), which requires management to evaluate for each annual and interim reporting period whether there is substantial doubt about an entity's ability to continue as a going concern. The guidance will be effective for annual and quarterly periods beginning on or after December 15, 2016, with early adoption permitted. We are currently developing processes and controls to adopt this guidance by the adoption deadline and do not expect the adoption of this guidance to have a material impact on our financial position, results of operations or stockholders' equity. In April 2015, the FASB issued a new accounting standard (ASU 2015-03, Interest- Imputation of Interest (Subtopic 835-30), which simplifies the presentation of debt issuance costs. The guidance will be effective for annual and quarterly periods beginning on January 1, 2016, with early adoption permitted. We do not expect the adoption of this guidance to have a material impact on our financial position.
Reclassifications	Reclassifications Certain prior period amounts, including amounts related to the adoption of ASU 2014-01 and ASU 2015-02, have been reclassified to conform to current period presentations.

Disclosure of accounting policy for consolidation to describe the significant judgments and assumptions made in determining whether a variable interest held by the entity requires the variable interest entity to be consolidated and (or) disclose information about its involvement with the variable interest entity; the methodology used by the entity for determining whether or not it is the primary beneficiary of the variable interest entity; and the significant factors considered and judgments made in determining that the power to direct the activities that significantly impact the economic performance of the variable interest entity are shared (as defined).