Share-based compensation (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Share-based Payment Arrangement, Noncash Expense [Abstract]
Total grant date fair value of stock awards vested	$ 119,335	$ 109,557	$ 93,359
Total gross compensation recognized for stock awards	139,675	104,424	94,748
Capitalized stock compensation	$ 56,817	$ 46,684	$ 46,079
Shares reserved for granting of future options and share awards	2,708,800
Vesting period	4 years
Fair value assumptions, expected term	3 years	2 years 9 months 18 days	3 years
Fair value assumptions, weighted average volatility rate (percent)	32.00%	30.00%	29.00%
Fair value assumptions, expected dividend rate (percent)	2.80%	2.50%	2.80%
Fair value assumptions, risk free interest rate (percent)	4.22%	2.47%	0.23%
Unrecognized compensation related to nonvested share awards	$ 260,400
Unrecognized compensation recognition period (in years)	4 years
Weighted average period recognition period for unrecognized compensation	22 months
General and Administrative Expense \| Executive Officer
Share-based Payment Arrangement, Noncash Expense [Abstract]
Share-Based Payment Arrangement, Accelerated Cost	$ 4,600
General and Administrative Expense \| Chief Financial Officer
Share-based Payment Arrangement, Noncash Expense [Abstract]
Share-Based Payment Arrangement, Accelerated Cost	$ 15,600
Restricted Stock
Share-based Payment Arrangement, Noncash Expense [Abstract]
Holding period	1 year
Restricted Stock issued prior to March 23, 2018
Share-based Payment Arrangement, Noncash Expense [Abstract]
Decrease in share reserve for each restricted share issued (in shares)	3
Restricted Stock issued on or after March 23, 2018
Share-based Payment Arrangement, Noncash Expense [Abstract]
Decrease in share reserve for each restricted share issued (in shares)	1
Stock Award
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Outstanding, beginning balance (in shares)	2,087,521	1,823,460	1,825,280
Number of shares granted	1,522,058	1,032,731	740,920
Number of shares vested	(798,729)	(749,101)	(709,737)
Number of shares forfeited	(56,689)	(19,569)	(33,003)
Outstanding, ending balance (in shares)	2,754,161	2,087,521	1,823,460
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Roll Forward]
Weighed average grant date fair value per share, outstanding beginning balance	$ 149.96	$ 150.89	$ 132.95
Weighed average grant date fair value per share, granted	108.22	141.58	174.32
Weighed average grant date fair value per share, vested	149.41	146.25	131.54
Weighed average grant date fair value per share, forfeited	104.65	160.83	99.55
Weighed average grant date fair value per share, outstanding ending balance	$ 127.34	$ 149.96	$ 150.89

Decrease In Share Reserve For Each Restricted Share Issued

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Represents the weighted average period over which unrecognized compensation cost is expected to be recognized for equity-based compensation plans.

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Share-Based Compensation Arrangement By Share-Based Payment Award, Award Holding Period After Vesting

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

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Amount of cost capitalized for award under share-based payment arrangement.

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

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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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Amount of additional cost recognized for award under share-based payment arrangement from occurrence of event accelerating recognition of cost.

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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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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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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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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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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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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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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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The risk-free interest rate assumption that is used in valuing an option on its own shares.

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Rate of weighted-average expected volatility for award under share-based payment arrangement.

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Number of shares authorized for issuance under share-based payment arrangement.

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Expected term of 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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