Average Share Price Per Share

No definition available.

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- Definition

Represents the minimum amount of convertible preferred operating partnership units which will be settled in cash upon conversion.

+ References

No definition available.

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- Definition

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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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

Including the current and noncurrent portions, carrying amount of debt identified as being convertible into another form of financial instrument (typically the entity's common stock) as of the balance sheet date, which originally required full repayment more than twelve months after issuance or greater than the normal operating cycle of the company.

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- Definition

The price per share of the conversion feature embedded in the debt instrument.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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- Definition

Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of convertible debt securities using the if-converted method.

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Earnings Per Common Share - Additional Information (Detail) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017	Sep. 30, 2015	Jun. 21, 2013
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Average share price (in dollars per share)	$ 92.83	$ 77.84	$ 90.09	$ 76.67
Principal amount of notes outstanding	$ 560,613,000		$ 560,613,000		$ 604,276,000
Exchangeable Senior Notes 2.375% due 2033 (the 2013 Notes)
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Principal amount of notes outstanding	$ 0		$ 0		49,259,000
Debt stated interest rate							2.375%
Shares related to the Notes included in the computation for diluted earnings per share (in shares)	0	413,498	0	413,498
Exchangeable Senior Notes 3.125% due 2035 (the 2015 Notes)
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Principal amount of notes outstanding	$ 575,000,000		$ 575,000,000		$ 575,000,000
Debt stated interest rate	3.125%		3.125%			3.125%
Exchange price (in dollars per share)	$ 93.06		$ 93.06
Shares related to the Notes included in the computation for diluted earnings per share (in shares)	0	0	0	0
Series A Units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Exchangeable preferred operating partnership units settled in cash, minimum	$ 101,700,000		$ 101,700,000
Stock Options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from computation of earnings per common share (in shares)	0	45,438	36,404	97,697