Cumulative Shares Issued

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- Definition

The weighted average time period over which the compensation expense for unvested restricted shares is expected to be recognized.

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- Definition

Payments In Lieu Of Dividends That Are Unvested, Recorded In Compensation Expense

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- Definition

Payments In Lieu Of Dividends That Vested, Recorded In Retained Earnings

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- Definition

Restricted Stock Issued Under Plan

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Authorized Current

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- Definition

Stock options issued under plan

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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- Definition

The number of shares converted in a noncash (or part noncash) transaction. Noncash is defined as transactions during a period that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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- Definition

The per share amount of a dividend declared, but not paid, as of the financial reporting date.

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- Definition

Aggregate cash paid by the entity during the period to settle equity instruments granted under equity-based payment arrangements.

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- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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- Definition

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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- Definition

Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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- Definition

Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

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- Definition

Amount of cash inflow from exercise of option under share-based payment arrangement.

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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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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.

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Stock Based Compensation Plans (Narrative) (Details) - USD ($) $ / shares in Units, $ in Thousands		1 Months Ended	12 Months Ended
	Dec. 18, 2020	Nov. 30, 2020	Oct. 31, 2020	Oct. 31, 2019	Oct. 31, 2018	Dec. 04, 2020	Nov. 23, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation cost related to unvested awards, not yet recognized			$ 37,500
Weighted-average period over which compensation cost related to unvested stock options is expected to be recognized (in years)			2 years 3 months 18 days
Total income tax benefits recognized for stock-based compensation arrangements			$ 58,200	$ 21,300	$ 21,700
Cash received from exercises of stock options			105,600	43,500	68,400
Total stock-based compensation expense			$ 239,286	91,913	88,055
Special dividends payable amount per share							$ 4.25
Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			3 years
Granted, shares			0
Restricted Stock Units [Member] \| Subsequent Event [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted, shares	100,000	1,700,000
Granted, weighted-average grant date fair value ($ per share)	$ 65.29	$ 60.43
Special dividends payable amount per share	$ 4.25
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			5 years
Granted, shares			1,694,000
Granted, weighted-average grant date fair value ($ per share)			$ 46.36
Total stock-based compensation expense			$ 140,700
Restricted Stock [Member] \| Subsequent Event [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Special dividends payable amount per share							$ 4.25
Payments in lieu of dividends that are unvested, recorded in compensation expense							$ 7,500
Deferred Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			5 years
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			5 years
Option expiration period			10 years
Stock Options [Member] \| Subsequent Event [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Special dividends payable amount per share						$ 4.25
Payments in lieu of special dividends that vested, recorded in retained earnings						$ 42,300
Payments in lieu of dividends that are unvested, recorded in compensation expense						$ 25,100
Omnibus Incentive Plan 2013 [Member] \| Non-Voting Common Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for future issuance under the plan, current			34,500,000
Restricted stock issued under plan			11,100,000
Stock options issued under plan			17,900,000
Cumulative Shares Issued			100,000
Omnibus Incentive Plan 2013 [Member] \| Deferred Stock Units [Member] \| Director [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation cost related to unvested restricted share awards not yet recognized			$ 3,200	1,700
Cash paid to settle deferred stock unit award liabilities			$ 200	$ 500	$ 400
Atlanta Capital Long-Term Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average period over which compensation cost related to restricted shares is expected to be recognized (in years)			3 years 2 months 12 days
Parametric Phantom Incentive Plan 2016 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Conversion of stock shares converted			1
Parametric Phantom Incentive Plan 2018 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Conversion of stock shares converted			0.01