Average Share Price Per Share

No definition available.

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- Definition

Earnings Per Share [Line Items]

+ References

No definition available.

+ Details

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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.

+ Details

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6928298&loc=SL6031898-161870

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

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- Details

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Earnings Per Common Share - Additional Information (Detail) - USD ($)	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017	Sep. 30, 2015	Jun. 21, 2013
Earnings Per Share [Line Items]
Average share price (in dollars per share)	$ 84.11	$ 75.47
Principal amount of notes outstanding	$ 568,644,000		$ 604,276,000
Operating Partnership [Member] \| Exchangeable Senior Notes 2.375% due 2033 (the 2013 Notes) [Member]
Earnings Per Share [Line Items]
Principal amount of notes outstanding	$ 11,555,000		49,259,000
Debt stated interest rate	2.375%				2.375%
Exchange price (in dollars per share)	$ 52.82
Shares related to the Notes included in the computation for diluted earnings per share (in shares)	81,382	336,848
Operating Partnership [Member] \| Exchangeable Senior Notes 3.125% due 2035 (the 2015 Notes) [Member]
Earnings Per Share [Line Items]
Principal amount of notes outstanding	$ 575,000,000		$ 575,000,000
Debt stated interest rate	3.125%			3.125%
Exchange price (in dollars per share)	$ 93.60
Shares related to the Notes included in the computation for diluted earnings per share (in shares)	0	0
Stock Options [Member]
Earnings Per Share [Line Items]
Anti-dilutive securities excluded from computation of earnings per common share (in shares)	40,956	103,854
Series A Units
Earnings Per Share [Line Items]
Exchangeable preferred operating partnership units settled in cash, minimum	$ 101,700,000