Regulation and Capital Adequacy - Risk-based Capital Ratios (Detail) $ in Millions	Jun. 30, 2021 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Standardized Capital Rules [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
CET1 capital	$ 89,440	$ 81,641	$ 74,850
Tier 1 capital	98,514	92,730	85,440
Tier 2 capital	14,965	15,424	14,925
Total capital	113,479	108,154
RWAs	$ 621,335	$ 554,162	563,575
CET1 capital ratio	0.144	0.147
Tier 1 capital ratio	0.159	0.167
Total capital ratio	0.183	0.195
Advanced Capital Rules [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
CET1 capital	$ 89,440	$ 81,641	74,850
Tier 1 capital	98,514	92,730	85,440
Tier 2 capital	12,747	13,279	13,473
Total capital	111,261	106,009
RWAs	$ 667,143	$ 609,750	$ 544,653
CET1 capital ratio	0.134	0.134
Tier 1 capital ratio	0.148	0.152
Total capital ratio	0.167	0.174
GS Bank USA [Member] | Standardized Capital Rules [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
CET1 capital	$ 32,593	$ 30,656
Tier 1 capital	32,593	30,656
Tier 2 capital	6,148	6,288
Total capital	38,741	36,944
RWAs	$ 295,470	$ 266,153
CET1 capital ratio	0.110	0.115
Tier 1 capital ratio	0.110	0.115
Total capital ratio	0.131	0.139
GS Bank USA [Member] | Advanced Capital Rules [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
CET1 capital	$ 32,593	$ 30,656
Tier 1 capital	32,593	30,656
Tier 2 capital	4,688	4,903
Total capital	37,281	35,559
RWAs	$ 193,398	$ 165,799
CET1 capital ratio	0.169	0.185
Tier 1 capital ratio	0.169	0.185
Total capital ratio	0.193	0.214