Federal Home Loan Bank, Advances, General Debt Obligations, Disclosure, Weighted Average Interest Rate, Variable

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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Amount of assets pledged to secure a debt instrument.

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Amount of advances or credit lines available from the Federal Home Loan Bank (FHLB).

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Amount of the collateral pledged in support of federal home loan bank advances outstanding.

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States the interest rate applicable to Federal Home Loan Bank advances outstanding as of the Balance Sheet date.

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Amount of Federal Home Loan Bank (FHLB) advances which have fixed interest.

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Amount of Federal Home Loan Bank (FHLB) advances which have floating interest rates.

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Federal Home Loan Bank (FHLB) stock represents an equity interest in a FHLB. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity).

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount of cash outflow for payment of an obligation from a lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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FEDERAL HOME LOAN BANK ADVANCES - Additional Information (Details) - USD ($)	Jun. 30, 2017	Dec. 31, 2018	Dec. 31, 2017
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Fixed bank advances		$ 805,000,000	$ 550,000,000
Company advances weighted average interest rate		2.56%
Variable bank advances		$ 715,000,000	$ 1,150,000,000
FHLB variable-rate, weighted average interest rate			1.40%
Advances from FHLB collateralized		4,050,000,000	$ 2,900,000,000
Amount of additional available borrowing		1,350,000,000
Line of Credit Facility [Line Items]
Securities sold under repurchase agreements		0	0
Federal Reserve Bank Advances
Line of Credit Facility [Line Items]
Amount of available line of credit with Federal Reserve Bank		60,600,000
Other borrowings		0
Securities Pledged as Collateral
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Advances from FHLB collateralized		0	405,600,000
Securities Pledged as Collateral \| Federal Reserve Bank Advances
Line of Credit Facility [Line Items]
Collateral on line of credit facility		78,800,000
Line of Credit \| Unsecured Federal Funds Line of Credit
Line of Credit Facility [Line Items]
Amount of available line of credit with Federal Reserve Bank		210,000,000
Line of Credit \| Line Of Credit Facility Maturing April 18, 2017
Line of Credit Facility [Line Items]
Amount of available line of credit with Federal Reserve Bank	$ 75,000,000
Repayments of lines of credit	$ 50,000,000
Federal Home Loan Bank of San Francisco
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
FHLB stock		$ 41,000,000	$ 48,700,000
London Interbank Offered Rate (LIBOR) \| Line of Credit \| Line of Credit Facility Maturing March 28, 2016
Line of Credit Facility [Line Items]
Basis spread on variable rate	2.25%
Minimum
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Company advances weighted average interest rate		1.61%	1.23%
Maximum
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Company advances weighted average interest rate		3.32%	3.00%
Weighted Average
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Company advances weighted average interest rate		2.58%	2.02%