Change in Equity Method Investment [Roll Forward]

No definition available.

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- Definition

Amount after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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- Definition

Amount of income (loss) for proportionate share of equity method investee's income (loss).

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- Definition

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

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- Definition

Value of units that were previously issued and have been repurchased during the year.

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- Definition

Value of units that were previously issued and then were repurchased and classified as treasury units. This element represents the monetary value of these units which were reissued during the period.

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- Definition

The distributions of earnings to an entity that is affiliated with the reporting entity by means of direct or indirect ownership.

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- Definition

The cash outflow associated with the acquisition of or advances to an entity that is related to it but not strictly controlled (for example, an unconsolidated subsidiary, affiliate, and joint venture or equity method investment) or the acquisition of an additional interest in a subsidiary (controlled entity).

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The cash inflow from an entity that is affiliated with the entity by means of direct or indirect ownership.

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- Definition

Dividends received on equity and other investments during the current period.

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- Definition

Value, after forfeiture, of shares issued under share-based payment arrangement. Excludes employee stock ownership plan (ESOP).

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- Definition

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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Investment in AB (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
Investment in AB (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Change in Equity Method Investment
Investment in AB as of January 1,				$ 1,490,701				$ 1,544,704	$ 1,490,701	$ 1,544,704
Equity in net income attributable to AB Unitholders	$ 87,909	$ 66,722	$ 59,023	$ 52,638	$ 66,759	$ 72,802	$ 65,388	$ 65,698	266,292	270,647	$ 232,393
Changes in accumulated other comprehensive (loss) income									(1,167)	(5,998)	8,562
Cash distributions received from AB									(249,463)	(308,042)	(226,846)
Additional investments with proceeds from exercises of compensatory options to buy AB Holding Units									11,511	16,589	20,110
Capital contributions to AB									270		22
Capital contributions from AB										(1,440)
AB Holding Units retired									(110,752)	(194,544)	(162,206)
AB Holding Units issued to fund long-term incentive compensation plans									146,488	168,955	135,604
Change in AB Holding Units held by AB for long-term incentive compensation plans									323
Change in AB Holding Units held by AB for long-term incentive compensation plans										(12,585)
Investment in AB as of December 31,	1,554,203				1,490,701				1,554,203	1,490,701	$ 1,544,704
ASU 2016-01
Change in Equity Method Investment
Impact of ASU adoption	0				(133)				0	(133)
Difference between Revenue Guidance in Effect before and after Topic 606 \| ASU 2014-09
Change in Equity Method Investment
Impact of ASU adoption	$ 0				$ 12,548				$ 0	$ 12,548