Regulatory Capital and Restrictions (Information On The Capital Ratios) (Detail) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2022 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2022 USD ($)	Sep. 30, 2021 USD ($)	Dec. 31, 2021 USD ($)
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
CET1 risk-based capital, Actual Amount	$ 5,637,725		$ 5,637,725		$ 2,804,290
CET1 risk-based capital, Actual Ratio	0.1080		0.1080		0.1172
CET1 risk-based capital, Minimum Requirement Amount	$ 2,348,463		$ 2,348,463		$ 1,076,871
CET1 risk-based capital, Well Capitalized Amount	3,392,224		3,392,224		1,555,480
Total risk-based capital, Actual Amount	$ 6,984,237		$ 6,984,237		$ 3,265,064
Total risk-based capital, Actual Ratio	0.1338		0.1338		0.1364
Total risk-based capital, Capital Requirements, Minimum Amount	$ 4,175,045		$ 4,175,045		$ 1,914,436
Total risk-based capital, Capital Requirements, Minimum Ratio	0.080		0.080		0.080
Total risk-based capital, Capital Requirements, Well Capitalized Amount	$ 5,218,807		$ 5,218,807		$ 2,393,046
Total risk-based capital, Capital Requirements, Well Capitalized Ratio	0.100		0.100		0.100
Tier 1 capital, Actual Amount	$ 5,921,704		$ 5,921,704		$ 2,949,327
Tier 1 capital, Actual Ratio	0.1135		0.1135		0.1232
Tier 1 capital, Capital Requirements, Minimum Amount	$ 3,131,284		$ 3,131,284		$ 1,435,827
Tier 1 capital, Capital Requirements, Minimum Ratio	0.060		0.060		0.060
Tier 1 capital, Capital Requirements, Well Capitalized Amount	$ 4,175,045		$ 4,175,045		$ 1,914,436
Tier 1 capital, Capital Requirements, Well Capitalized Ratio	0.080		0.080		0.080
Tier 1 leverage capital ratio, Actual Amount	$ 5,921,704		$ 5,921,704		$ 2,949,327
Tier 1 leverage capital ratio, Actual Ratio	0.0898		0.0898		0.0847
Tier 1 leverage capital ratio, Capital Requirements, Minimum Amount	$ 2,637,840		$ 2,637,840		$ 1,393,607
Tier 1 leverage capital ratio, Capital Requirements, Minimum Ratio	0.040		0.040		0.040
Tier 1 leverage capital ratio, Capital Requirements, Well Capitalized Amount	$ 3,297,301		$ 3,297,301		$ 1,742,008
Tier 1 leverage capital ratio, Capital Requirements, Well Capitalized Ratio	0.050		0.050		0.050
Dividends paid	$ 250,000	$ 40,000	$ 375,000	$ 160,000
Subsidiaries
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
CET1 risk-based capital, Actual Amount	$ 6,487,577		$ 6,487,577		$ 3,034,883
CET1 risk-based capital, Actual Ratio	0.1246		0.1246		0.1269
CET1 risk-based capital, Minimum Requirement Amount	$ 2,342,827		$ 2,342,827		$ 1,075,920
CET1 risk-based capital, Well Capitalized Amount	3,384,084		3,384,084		1,554,107
Total risk-based capital, Actual Amount	$ 6,957,328		$ 6,957,328		$ 3,273,300
Total risk-based capital, Actual Ratio	0.1336		0.1336		0.1369
Total risk-based capital, Capital Requirements, Minimum Amount	$ 4,165,026		$ 4,165,026		$ 1,912,747
Total risk-based capital, Capital Requirements, Minimum Ratio	0.080		0.080		0.080
Total risk-based capital, Capital Requirements, Well Capitalized Amount	$ 5,206,283		$ 5,206,283		$ 2,390,934
Total risk-based capital, Capital Requirements, Well Capitalized Ratio	0.100		0.100		0.100
Tier 1 capital, Actual Amount	$ 6,487,577		$ 6,487,577		$ 3,034,883
Tier 1 capital, Actual Ratio	0.1246		0.1246		0.1269
Tier 1 capital, Capital Requirements, Minimum Amount	$ 3,123,770		$ 3,123,770		$ 1,434,560
Tier 1 capital, Capital Requirements, Minimum Ratio	0.060		0.060		0.060
Tier 1 capital, Capital Requirements, Well Capitalized Amount	$ 4,165,026		$ 4,165,026		$ 1,912,747
Tier 1 capital, Capital Requirements, Well Capitalized Ratio	0.080		0.080		0.080
Tier 1 leverage capital ratio, Actual Amount	$ 6,487,577		$ 6,487,577		$ 3,034,883
Tier 1 leverage capital ratio, Actual Ratio	0.0985		0.0985		0.0872
Tier 1 leverage capital ratio, Capital Requirements, Minimum Amount	$ 2,634,102		$ 2,634,102		$ 1,392,821
Tier 1 leverage capital ratio, Capital Requirements, Minimum Ratio	0.040		0.040		0.040
Tier 1 leverage capital ratio, Capital Requirements, Well Capitalized Amount	$ 3,292,628		$ 3,292,628		$ 1,741,026
Tier 1 leverage capital ratio, Capital Requirements, Well Capitalized Ratio	0.050		0.050		0.050
Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
CET1 risk-based capital, Actual Ratio	0.045		0.045		0.045
Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets \| Subsidiaries
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
CET1 risk-based capital, Actual Ratio	0.045		0.045		0.045
Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
CET1 risk-based capital, Actual Ratio	0.065		0.065		0.065
Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets \| Subsidiaries
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
CET1 risk-based capital, Actual Ratio	0.065		0.065		0.065

Amount of total capital as defined by regulatory framework.

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Amount of minimum total risk-based capital required for capital adequacy as defined by regulatory framework.

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This element represents disclosure of the total aggregate cash dividends paid to the entity by consolidated subsidiaries, by unconsolidated subsidiaries, and by 50 percent or less owned persons accounted for using the equity method.

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Amount of Common Equity Tier 1 risk-based capital as defined by regulatory framework.

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Amount of Tier 1 leverage capital as defined by regulatory framework.

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