Noninterest Income Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Disaggregation of Revenue [Line Items]
Brokerage Commissions Revenue	$ 31,202	$ 22,424
Fees and Commissions, Credit and Debit Cards, Gross of Rebates	29,548
Merchant Discount Fees	2,906	2,740
Deposit service charges	17,699	13,975
Client investment fees	22,875	9,026
Fund Management Fees	5,736	5,169
Correspondent bank fees	1,396
Revenue from Contract with Customer, Excluding Assessed Tax	111,362
Noninterest Income, Other Operating Income	44,156
Noninterest income	155,518	117,659
Global Commercial Bank
Disaggregation of Revenue [Line Items]
Brokerage Commissions Revenue	30,972
Fees and Commissions, Credit and Debit Cards, Gross of Rebates	29,449
Merchant Discount Fees	2,906
Deposit service charges	17,040
Client investment fees	10,250
Fund Management Fees	0
Correspondent bank fees	1,396
Revenue from Contract with Customer, Excluding Assessed Tax	92,013
Noninterest Income, Other Operating Income	7,333
Noninterest income	99,346	79,519
SVB Private Bank
Disaggregation of Revenue [Line Items]
Brokerage Commissions Revenue	179
Fees and Commissions, Credit and Debit Cards, Gross of Rebates	0
Merchant Discount Fees	0
Deposit service charges	28
Client investment fees	302
Fund Management Fees	0
Correspondent bank fees	0
Revenue from Contract with Customer, Excluding Assessed Tax	509
Noninterest Income, Other Operating Income	(2)
Noninterest income	507	718
SVB Capital
Disaggregation of Revenue [Line Items]
Brokerage Commissions Revenue	0
Fees and Commissions, Credit and Debit Cards, Gross of Rebates	0
Merchant Discount Fees	0
Deposit service charges	0
Client investment fees	0
Fund Management Fees	5,736
Correspondent bank fees	0
Revenue from Contract with Customer, Excluding Assessed Tax	5,736
Noninterest Income, Other Operating Income	23,174
Noninterest income	28,910	16,775
Other Items
Disaggregation of Revenue [Line Items]
Brokerage Commissions Revenue	51
Fees and Commissions, Credit and Debit Cards, Gross of Rebates	99
Merchant Discount Fees	0
Deposit service charges	631
Client investment fees	12,323
Fund Management Fees	0
Correspondent bank fees	0
Revenue from Contract with Customer, Excluding Assessed Tax	13,104
Noninterest Income, Other Operating Income	13,651
Noninterest income	$ 26,755	$ 20,647

Correspondent Bank Rebates

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Fees and Commissions, Credit and Debit Cards, Gross of Rebates

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Fees earned as the general partner of managed funds of funds

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Amount of fixed fee revenue for the management of an investment fund portfolio. Excludes investment advisory, distribution and servicing, and performance fees.

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Amount of commission revenue from buying and selling securities on behalf of customers.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 940
-SubTopic 20
-Section 05
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Includes amounts charged depositors for: (1) maintenance of their accounts (maintenance charges); (2) failure to maintain specified minimum balances on account; (3) exceeding the number of checks or transactions allowed to be processed in a given period; (4) checks drawn on no minimum balance deposit accounts; (5) withdrawals from nontransaction deposit accounts; (6) closing savings accounts before a specified minimum period of time has elapsed; (7) accounts which have remained inactive for extended periods of time or which have become dormant; (8) use of automated teller machines or remote service units; (9) checks drawn against insufficient funds that the bank assesses regardless of whether it decides to pay, return or hold the check; (10) issuing stop payment orders; (11) certifying checks; and (12) accumulating or disbursing funds deposited in IRAs or Keogh Plan accounts when not handled by the bank's trust department. This item does not include penalties assessed on the early withdrawal of time deposits.

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Amount of earnings on fees charged to merchants for the cardholder's use of a credit card. Excludes interest income earned on credit card balances, transactions and credit card services including late, over limit, and annual fees.

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The total amount of noninterest income which may be derived from: (1) fees and commissions; (2) premiums earned; (3) insurance policy charges; (4) the sale or disposal of assets; and (5) other sources not otherwise specified.

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Amount of revenue earned, classified as other, excluding interest income.

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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-Publisher FASB
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