Business Combination, Consideration Transferred, Bond Exchanged Amount

No definition available.

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- Definition

Business Combination, Consideration Transferred, Bond Exchanged, Fair Value

+ 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

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

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 23
-URI http://asc.fasb.org/extlink&oid=84229725&loc=d3e1043-128460

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Balance Type:	debit
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- Definition

Amount of liabilities incurred by the acquirer as part of consideration transferred in a business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 25
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6911189&loc=d3e6405-128476

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6578-128477

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6613-128477

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- 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

+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3179-108585

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Balance Type:	debit
Period Type:	duration

- Definition

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

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

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

+ References

No definition available.

+ Details

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3213-108585

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- Definition

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

+ References

+ Details

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Acquisitions - Narrative (Details) $ in Millions				6 Months Ended	9 Months Ended	12 Months Ended			36 Months Ended
Acquisitions - Narrative (Details) $ in Millions	Jan. 10, 2017 USD ($)	Jul. 01, 2016 USD ($)	Apr. 01, 2015 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2017 USD ($) Company
Business Acquisition [Line Items]
Number of business acquired \| Company									3
Acquisitions, net of cash acquired						$ 95.0	$ (435.0)	$ (800.0)
Net par amount outstanding				$ 296,318.0		264,952.0	$ 296,318.0		$ 264,952.0
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
Radian [Member]
Business Acquisition [Line Items]
Cash purchase price			$ 804.0
Net par amount outstanding assumed in business acquisition			13,600.0
Revenue					$ 560.0
Net income (loss)					366.0
Acquisition related costs					$ 12.0
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
Subsidiaries [Member] \| CIFG Holding Inc. [Member]
Business Acquisition [Line Items]
Cash purchase price		450.6
Subsidiaries [Member] \| Radian [Member]
Business Acquisition [Line Items]
Cash purchase price			804.5
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]
Ownership percentage by noncontrolling owners		1.60%
Acquisitions, net of cash acquired		$ 7.1
AGUS [Member] \| Subsidiaries [Member] \| Radian [Member]
Business Acquisition [Line Items]
Acquisition loan from parent company			$ 200.0