Business Combination, Consideration Transferred, Bond Exchanged Amount

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- Definition

Business Combination, Consideration Transferred, Bond Exchanged, Fair Value

+ References

No definition available.

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- Definition

Represents the outstanding principal amounts of the underlying insured obligations that are accounted for as credit derivatives, net of protection purchased.

+ References

No definition available.

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- Definition

Guarantor Obligations, Net Expected Loss To Be Paid After Recoveries For Representations And Warranties On Business Combinations

+ References

No definition available.

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- Definition

Represents the outstanding principal amounts of the underlying insured obligations for financial guaranty contracts, after netting out ceded contracts.

+ References

No definition available.

+ Details

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- Definition

Represents the outstanding principal amounts of the underlying insured obligations for financial guaranty contracts, after netting out ceded contracts.

+ References

No definition available.

+ Details

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- Definition

Reinsurance Retention Policy, Quota Share Basis, Percent

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

+ References

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-Publisher FASB
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-Topic 805
-SubTopic 10
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-Paragraph 23
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- Definition

This element represents the amount of earnings or loss of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

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- Definition

This element represents the amount of revenue of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

+ References

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- Definition

Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Excludes cash and cash equivalents within disposal group and discontinued operation.

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- Definition

The cash inflow associated with the acquisition of business during the period (for example, cash that was held by the acquired business).

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- Definition

Fair value of credit risk derivative asset after deduction of credit risk derivative liability.

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- Definition

Amount of new business written on financial guarantee insurance contracts.

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- Definition

Amount of cash inflow from premiums received for premium receivable on financial guarantee insurance contracts.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

+ References

No definition available.

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- Definition

The number of businesses acquired by the entity during the period.

+ References

No definition available.

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- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

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- Definition

The carrying amount as of the balance sheet date due the entity from (a) agents and insureds, (b) uncollected premiums and (c) others, net of the allowance for doubtful accounts.

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- Definition

A fee charged for services from professionals such as doctors, lawyers and accountants. The term is often expanded to include other professions, for example, pharmacists charging to maintain a medicinal profile of a client or customer.

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Assumption of Insured Portfolio and Business Combinations - Narrative (Details) $ in Millions				6 Months Ended	12 Months Ended			36 Months Ended
	Jun. 01, 2018 USD ($)	Jan. 10, 2017 USD ($)	Jul. 01, 2016 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2017 USD ($) Company
Business Acquisition [Line Items]
Number of business acquired \| Company								2
Acquisition, net of cash acquired					$ 0.0	$ 95.0	$ (435.0)
Net par amount outstanding					241,802.0	264,952.0		$ 264,952.0
Net Par Outstanding					6,182.0	6,207.0		6,207.0
Gross written premiums on new business, net of commissions					610.0	301.0	193.0
Financial Guarantee Insurance Contracts, Premium Receivable, Proceeds from Premiums Received					577.0	301.0	$ 258.0
Cash					104.0	144.0		144.0
Premiums receivable, net of commissions payable					904.0	915.0		915.0
Fair value of credit derivative asset (liability), net					(207.0)	(269.0)		$ (269.0)
Net expected loss to be paid					131.0	21.0
CIFG Holding Inc. [Member]
Business Acquisition [Line Items]
Cash purchase price			$ 443.0
Revenue				$ 307.0
Net income (loss)				323.0
Acquisition related costs				$ 6.0
MBIA UK [Member]
Business Acquisition [Line Items]
Cash purchase price		$ 334.0
Revenue						192.0
Net income (loss)						139.0
Acquisition related costs						7.0
Net expected loss to be paid					$ 0.0	$ 21.0
Subsidiaries [Member] \| CIFG Holding Inc. [Member]
Business Acquisition [Line Items]
Cash purchase price			450.6
Subsidiaries [Member] \| MBIA UK [Member]
Business Acquisition [Line Items]
Cash acquired from acquisition		23.0
Bond exchanged amount		347.0
Gross Par Outstanding, Fair Value		334.0
CIFG Holding Inc. [Member]
Business Acquisition [Line Items]
Net par amount outstanding assumed in business acquisition			4,200.0
MBIA UK [Member]
Business Acquisition [Line Items]
Net par amount outstanding		$ 12,000.0
AGUS [Member] \| CIFG Holding Inc. [Member]
Business Acquisition [Line Items]
Acquisition, net of cash acquired			$ 7.1
AGUS [Member] \| AGUS [Member] \| CIFG Holding Inc. [Member]
Business Acquisition [Line Items]
Ownership percentage by noncontrolling owners			1.60%
Reinsurance of SGI Insured Portfolio [Member]
Business Acquisition [Line Items]
Gross written premiums on new business, net of commissions	$ 330.0
Financial Guarantee Insurance Contracts, Premium Receivable, Proceeds from Premiums Received	$ 275.0
Reinsurance of SGI Insured Portfolio [Member] \| AGC [Member]
Business Acquisition [Line Items]
Reinsurance Retention Policy, Quota Share Basis, Percent	100.00%				100.00%
Net par amount outstanding	$ 12,000.0
Cash	363.0
Premiums receivable, net of commissions payable	61.0
Professional Fees	4.0
United States [Member]
Business Acquisition [Line Items]
Net par amount outstanding					$ 196,506.0
United States [Member] \| Syncora Guarantee Inc [Member] \| Reinsurance of SGI Insured Portfolio [Member]
Business Acquisition [Line Items]
Net Par Outstanding	1,500.0
Fair value of credit derivative asset (liability), net	68.0
Insurance Contracts Assumed [Member] \| Reinsurance of SGI Insured Portfolio [Member] \| AGC [Member]
Business Acquisition [Line Items]
Cash	343.0
Premiums receivable, net of commissions payable	45.0
Fair value of credit derivative asset (liability), net	$ 17.0