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Fair value portion of deposit liabilities held by the entity, including, but not limited to, foreign and domestic, interest and noninterest bearing, demand deposits, saving deposits, negotiable orders of withdrawal (NOW) and time deposits.

No definition available.

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Fair value portion of borrowing from Federal Home Loan Bank (FHLBank).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.13(3)(a))
-URI https://asc.fasb.org/extlink&oid=126897435&loc=d3e534808-122878

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Fair value of financial obligations, including, but not limited to, debt instruments, derivative liabilities, federal funds purchased and sold under agreements to repurchase, securities loaned or sold under agreements to repurchase, financial instruments sold not yet purchased, guarantees, line of credit, loans and notes payable, servicing liability, and trading liabilities.

No definition available.

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Amount of investment in mortgage loan on real estate by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 948
-SubTopic 310
-Section S99
-Paragraph 1
-Subparagraph (SX 210.12-29(Column G))
-URI https://asc.fasb.org/extlink&oid=120402547&loc=d3e617274-123014

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Carrying amount of loans made to policyholders against the cash surrender value (CSV) or other policyholder funds, and secured by the CSV, policyholder funds or the death benefit provided by the insurance contracts.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.(a),1(e))
-URI https://asc.fasb.org/extlink&oid=126734703&loc=d3e572229-122910

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Fair value of financial assets as of the balance sheet date.

No definition available.

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Data Type:	xbrli:monetaryItemType
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The fair value amount of the coinsurer's funds withheld on its behalf under coinsurance agreements.

No definition available.

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Data Type:	xbrli:monetaryItemType
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Fair value portion of investment income due and accrued.

No definition available.

Name:	usac_InvestmentIncomeDueAndAccruedFairValueDisclosure
Namespace Prefix:	usac_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

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