Dividend Availability and Regulatory Matters Dividend Availability and Regulatory Matters (Details Textual)		12 Months Ended			36 Months Ended
	Apr. 30, 2021 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2020 USD ($)
Compliance with Regulatory Capital Requirements for Mortgage Companies [Line Items]
Proceeds from Dividends Received		$ 182,000,000
Retained earnings		1,016,350,000	$ 409,391,000		$ 409,391,000
Deferred Tax Assets, Regulatory Assets and Liabilities		$ 10,000
Capital Required for Capital Adequacy to Risk Weighted Assets		0.080
Tier One Leverage Capital Required for Capital Adequacy to Average Assets		0.060
Capital Required to be Well Capitalized to Risk Weighted Assets		0.1000	0.1000		0.1000
Tier One Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets		0.0800	0.0800		0.0800
Tier One Risk Based Capital Required to be Well Capitalized		6.50%	6.50%		6.50%
Tier One Leverage Capital Required to be Well Capitalized to Average Assets		0.050	0.0500		0.0500
Common Equity Tier One Capital Ratio		0.045
Supplementary Leverage Ratio		0.040
Subordinated debt		$ 863,300,000
Tier One Capital, Trust Preferred Securities Capital Portion		131,000,000
Tier Two Capital, Trust Preferred Securities Capital Portion		718,200,000
Net earnings (loss)		$ 606,959,000	$ (1,237,574,000)	$ 468,636,000
Capital Required to be Well Capitalized to Risk Weighted Assets Capital Conservation Buffer		10.50%	10.50%		10.50%
Tier One Risk Based Common Equity Required to be Well Capitalized to Risk Weighted Assets Capital Conservation Buffer		7.00%	7.00%		7.00%
Tier One Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets Capital Conservation Buffer		8.50%	8.50%		8.50%
April 30, 2021 Issuance
Compliance with Regulatory Capital Requirements for Mortgage Companies [Line Items]
Subordinated debt	$ 400,000,000
Subordinated Borrowing, Interest Rate	3.25%
Pacific Western Bank
Compliance with Regulatory Capital Requirements for Mortgage Companies [Line Items]
Retained earnings		$ 1,500,000,000
Deferred Tax Assets, Regulatory Assets and Liabilities		$ 41,000,000
Capital Required to be Well Capitalized to Risk Weighted Assets			0.1000		0.1000
Tier One Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets			0.0800		0.0800
Tier One Risk Based Capital Required to be Well Capitalized			6.50%		6.50%
Tier One Leverage Capital Required to be Well Capitalized to Average Assets			0.0500		0.0500
Net earnings (loss)					$ (155,300,000)
Payments of Ordinary Dividends					$ 776,000,000
Capital Required to be Well Capitalized to Risk Weighted Assets Capital Conservation Buffer		10.50%	10.50%		10.50%
Tier One Risk Based Common Equity Required to be Well Capitalized to Risk Weighted Assets Capital Conservation Buffer		7.00%	7.00%		7.00%
Tier One Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets Capital Conservation Buffer		8.50%	8.50%		8.50%