Represents the term used to determine historical loss component of allowance.

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Represents the percentage of ownership in cost-method investments.

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Represents the percentage of cash contributions during the period made by the entity to the Employee Stock Ownership Plan (ESOP).

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Represents the delinquency period for interest income on loans to be discontinued.

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Represents the number of active operating subsidiaries of the entity.

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Represents the number of retail-banking offices operated by the entity.

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Amount of addition to allowance reserve for credit loss arising from purchase of loan and lease portfolios.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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The cash outflow from (a) purchases of loans held-for-investment, (b) purchases of leases held-for-investment, and (c) both.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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The carrying amounts of cash and cash equivalent items which are restricted as to withdrawal or usage. Restrictions may include legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or entity statements of intention with regard to particular deposits; however, time deposits and short-term certificates of deposit are not generally included in legally restricted deposits. Excludes compensating balance arrangements that are not agreements which legally restrict the use of cash amounts shown on the balance sheet. This element is for unclassified presentations; for classified presentations there is a separate and distinct element.

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Summary of Significant Accounting Policies - (Details) $ in Thousands	1 Months Ended	12 Months Ended
	Dec. 31, 2015 USD ($)	Dec. 31, 2016 USD ($) item	Dec. 31, 2015 USD ($) item
Loans Receivable Held For Investment
Delinquency period for interest income on loans to be discontinued		90 days
Loans Purchased
Allowance for loan losses \| $		$ 0
Payments to Acquire Loans and Leases Held-for-investment \| $			$ 100,161
Allowance for Loan Losses
Term during which historical loss component of allowance is determined		3 years
Operating Segments
Number of active operating subsidiaries \| item		1	1
Number of Reportable Segments \| item		1
Maximum
Investment in Affordable Housing Limited Partnership
Ownership percentage		5.00%
Retirement Plans
Cash contributions (as a percent)		25.00%
Office buildings and improvements \| Minimum
Office Properties and Equipment
Property, Plant and Equipment, Useful Life		10 years
Office buildings and improvements \| Maximum
Office Properties and Equipment
Property, Plant and Equipment, Useful Life		40 years
Furniture, fixtures and equipment \| Minimum
Office Properties and Equipment
Property, Plant and Equipment, Useful Life		3 years
Furniture, fixtures and equipment \| Maximum
Office Properties and Equipment
Property, Plant and Equipment, Useful Life		10 years
Single family
Loans Purchased
Payments to Acquire Loans and Leases Held-for-investment \| $	$ 99,700
Deposits \| Long-time Customer
Concentration of Credit Risk
Concentration Risk, Percentage		11.00%
Federal Reserve Bank
Cash Flows
Restricted Cash and Cash Equivalents \| $		$ 0
Los Angeles, California
Nature of Operations and Principles of Consolidation
Number of retail-banking offices \| item		2
Nearby city of Inglewood, California
Nature of Operations and Principles of Consolidation
Number of retail-banking offices \| item		1