Reclassification from AOCI to Retained Earnings

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Number of shares issued during the period as a result of net share activity under the company's long-term incentive plan, employee stock purchase plan, and share cancellations in satisfaction of withholding tax requirements.

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Includes share-based compensation expense, net share activity under the company's long-term incentive plan, employee stock purchase plan, excess tax benefits for share-based compensation and share cancellations in satisfaction of withholding tax requirements.

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Amount of paid and unpaid common stock dividends declared with the form of settlement in cash.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount of increase in noncontrolling interest from subsidiary issuance of equity interests to noncontrolling interest holders.

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Amount after tax of other comprehensive income (loss) attributable to parent entity.

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Number of shares issued which are neither cancelled nor held in the treasury.

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Number of shares that have been repurchased and retired during the period.

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Equity impact of the value of stock that has been repurchased and retired during the period. The excess of the purchase price over par value can be charged against retained earnings (once the excess is fully allocated to additional paid in capital).

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Amount of stockholders' equity (deficit), net of receivables from officers, directors, owners, and affiliates of the entity, attributable to both the parent and noncontrolling interests. Amount excludes temporary equity. Alternate caption for the concept is permanent equity.

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This element represents movements included in the statement of changes in stockholders' equity which are not separately disclosed or provided for elsewhere in the taxonomy.

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Consolidated Statement of Shareholders' Equity - USD ($) $ in Millions	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income [Member]	Deferred Equity Compensation [Member]	Total Shareholders’ Equity Attributable to Assured Guaranty Ltd. [Member]	Noncontrolling Interest [Member]
Beginning balance (in shares) at Dec. 31, 2016		127,988,230
Beginning balance at Dec. 31, 2016	$ 6,504	$ 1	$ 1,060	$ 5,289	$ 149	$ 5	$ 6,504	$ 0
Increase (Decrease) in Shareholders' Equity
Net income (loss)	730			730			730
Dividends	(70)			(70)			(70)
Common stock repurchases (in shares)		(12,669,643)
Common stock repurchases	(501)	$ 0	(501)				(501)
Share-based compensation and other (in shares)		702,265
Share-based compensation	10	$ 0	14			(4)	10
Other comprehensive income (loss)	167				167		167
Effect of adoption of ASU 2016-01 (see Note 1)				(56)	56
Other	1			1			1
Ending balance (in shares) at Dec. 31, 2017		116,020,852
Ending balance at Dec. 31, 2017	6,839	$ 1	573	5,892	372	1	6,839	0
Increase (Decrease) in Shareholders' Equity
Net income (loss)	521			521			521
Dividends	(71)			(71)			(71)
Common stock repurchases (in shares)		(13,243,107)
Common stock repurchases	(500)	$ 0	(500)				(500)
Share-based compensation and other (in shares)		894,847
Share-based compensation	13		13			0	13
Other comprehensive income (loss)	(247)				(247)		(247)
Effect of adoption of ASU 2016-01 (see Note 1)				32	(32)
Ending balance (in shares) at Dec. 31, 2018		103,672,592
Ending balance at Dec. 31, 2018	6,555	$ 1	86	6,374	93	1	6,555	0
Increase (Decrease) in Shareholders' Equity
Net income (loss)	402			402			402
Dividends	(74)			(74)			(74)
Common stock repurchases (in shares)		(11,163,929)
Common stock repurchases	(500)	$ 0	(93)	(407)			(500)
Share-based compensation and other (in shares)		766,324
Share-based compensation	7	$ 0	7			0	7
Contributions	6							6
Other comprehensive income (loss)	249				249		249
Ending balance (in shares) at Dec. 31, 2019		93,274,987
Ending balance at Dec. 31, 2019	$ 6,645	$ 1	$ 0	$ 6,295	$ 342	$ 1	$ 6,639	$ 6