Parent Company Only Condensed Financial Information - Condensed Balance Sheets (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Assets:
Cash and cash equivalents	$ 14,619	$ 17,675
Investment securities	127,959	49,307
Loans, amortized cost	66,276	45,181
Lease right-of-use assets	313	210
Other assets	1,928	3,206
Total assets	211,478	115,511
Liabilities and total equity
Long-term debt	2,570	844
Lease liabilities	388	259
Other liabilities	2,587	3,972
Total liabilities	194,869	107,078
SVBFG stockholders' equity	16,236	8,220
Total liabilities and total equity	211,478	115,511
Parent Company
Assets:
Cash and cash equivalents	2,324	671
Investment securities	731	667
Loans, amortized cost	1	1
Lease right-of-use assets	82	99
Other assets	387	260
Total assets	19,214	9,434
Liabilities and total equity
Long-term debt	2,570	844
Lease liabilities	113	134
Other liabilities	295	236
Total liabilities	2,978	1,214
SVBFG stockholders' equity	16,236	8,220
Total liabilities and total equity	19,214	9,434
Parent Company | Bank Subsidiary
Assets:
Investment in subsidiaries	14,795	7,069
Parent Company | Nonbank Subsidiaries
Assets:
Investment in subsidiaries	$ 894	$ 667