Regulatory Capital (Tables)

12 Months Ended

Dec. 31, 2021

Banking and Thrift, Other Disclosures [Abstract]

Regulatory Capital Ratios

The following tables present the regulatory capital requirements under the applicable Basel III based U.S. capital rules:

Flagstar Bancorp	Actual				Minimum Capital Ratios				Well-Capitalized Under Prompt Corrective Action Provisions
	Amount		Ratio		Amount		Ratio		Amount		Ratio
	(Dollars in millions)
December 31, 2021
Tier 1 capital (to adjusted avg. total assets)	$	2,798	10.54	%	$	1,062	4.0	%	$	1,327	5.0	%
Common equity Tier 1 capital (to RWA)	2,558		13.19	%	873		4.5	%	1,261		6.5	%
Tier 1 capital (to RWA)	2,798		14.43	%	1,164		6.0	%	1,552		8.0	%
Total capital (to RWA)	3,080		15.88	%	1,552		8.0	%	1,940		10.0	%
December 31, 2020
Tier 1 capital (to adjusted avg. total assets)	$	2,270	7.71	%	$	1,178	4.0	%	$	1,472	5.0	%
Common equity Tier 1 capital (to RWA)	2,030		9.15	%	999		4.5	%	1,442		6.5	%
Tier 1 capital (to RWA)	2,270		10.23	%	1,331		6.0	%	1,775		8.0	%
Total capital (to RWA)	2,638		11.89	%	1,775		8.0	%	2,219		10.0	%

Flagstar Bank	Actual				Minimum Capital Ratios				Well-Capitalized Under Prompt Corrective Action Provisions
	Amount		Ratio		Amount		Ratio		Amount		Ratio
	(Dollars in millions)
December 31, 2021
Tier 1 capital (to adjusted avg. total assets)	$	2,706	10.21	%	$	1,060	4.0	%	$	1,325	5.0	%
Common equity Tier 1 capital (to RWA)	2,706		13.96	%	872		4.5	%	1,260		6.5	%
Tier 1 capital (to RWA)	2,706		13.96	%	1,163		6.0	%	1,551		8.0	%
Total capital (to RWA)	2,839		14.65	%	1,551		8.0	%	1,938		10.0	%
December 31, 2020
Tier 1 capital (to adjusted avg. total assets)	$	2,390	8.12	%	$	1,177	4.0	%	$	1,472	5.0	%
Common equity Tier 1 capital (to RWA)	2,390		10.77	%	999		4.5	%	1,443		6.5	%
Tier 1 capital (to RWA)	2,390		10.77	%	1,332		6.0	%	1,775		8.0	%
Total capital (to RWA)	2,608		11.75	%	1,775		8.0	%	2,219		10.0	%