Value of real estate assets, at cost, as of the balance sheet date that are subject to secured notes payable.

No definition available.

Name:	cpt_ValueOfRealEstateAssetsAtCostSubjectToSecuredNotes
Namespace Prefix:	cpt_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 6
-Subparagraph (a)
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
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-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

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(2))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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=119400593&loc=d3e572229-122910

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+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of uncollateralized debt obligations (with maturities initially due after one year or beyond the operating cycle if longer).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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Notes Payable (Summary Of Indebtedness) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Oct. 01, 2019	Jun. 06, 2019	Dec. 31, 2018
Unsecured Debt	$ 2,524,099,000			$ 1,836,427,000
Secured notes payable	0			485,176,000
Total notes payable	2,524,100,000			2,321,600,000
Value Of Real Estate Assets At Cost Subject To Secured Notes	0			867,900,000
Commercial Banks [Member]
Unsecured Debt	143,700,000			99,600,000
Senior Unsecured Notes [Member]
Unsecured Debt	2,380,400,000			1,736,800,000
2.70% Term loan Due 2022 \| Commercial Banks [Member]
Unsecured Debt	$ 99,700,000			$ 99,600,000
Notes payable, effective interest rate	2.70%			3.34%
Debt Instrument, Maturity Date	Jan. 01, 2022
4.78% Notes Due 2021 \| Senior Unsecured Notes [Member]
Unsecured Debt	$ 0	$ 250,000,000		$ 249,100,000
Notes payable, effective interest rate		4.78%		4.78%
Debt Instrument, Maturity Date	Jun. 15, 2021
3.15% Notes Due 2022 \| Senior Unsecured Notes [Member]
Unsecured Debt	$ 348,000,000.0			$ 347,300,000
Notes payable, effective interest rate	3.15%			3.15%
Debt Instrument, Maturity Date	Dec. 15, 2022
5.07% Notes Due 2023 \| Senior Unsecured Notes [Member]
Unsecured Debt	$ 248,400,000			$ 248,000,000.0
Notes payable, effective interest rate	5.07%			5.07%
Debt Instrument, Maturity Date	Jun. 15, 2023
4.36% Notes Due 2024 \| Senior Unsecured Notes [Member]
Unsecured Debt	$ 249,000,000.0			$ 248,700,000
Notes payable, effective interest rate	4.36%			4.36%
Debt Instrument, Maturity Date	Jan. 15, 2024
3.68% Notes Due 2024 \| Senior Unsecured Notes [Member]
Unsecured Debt	$ 248,000,000.0			$ 247,600,000
Notes payable, effective interest rate	3.68%			3.68%
Debt Instrument, Maturity Date	Sep. 15, 2024
3.74% Notes Due 2028 \| Senior Unsecured Notes [Member]
Unsecured Debt	$ 396,700,000			$ 396,100,000
Notes payable, effective interest rate	3.74%			3.74%
Debt Instrument, Maturity Date	Oct. 15, 2028
3.67% Notes due 2029 \| Senior Unsecured Notes [Member]
Unsecured Debt	$ 593,700,000			$ 0
Notes payable, effective interest rate	3.67%		3.179%	0.00%
Debt Instrument, Maturity Date	Jul. 01, 2029
3.41% Notes due 2049 \| Senior Unsecured Notes [Member]
Unsecured Debt	$ 296,600,000			$ 0
Notes payable, effective interest rate	3.41%	3.353%		0.00%
Debt Instrument, Maturity Date	Nov. 01, 2049
Secured Notes 4.38% Fixed Rate Mortgage Note Due 2045 [Member] \| Secured Debt [Member]
Secured notes payable	$ 0			$ 45,900,000
Notes payable, effective interest rate	0.00%			4.38%
Debt Instrument, Maturity Date	Sep. 01, 2045
Secured Notes 5.19% Fixed Rate Note Due 2019 [Member] \| Secured Debt [Member]
Secured notes payable	$ 0			$ 419,900,000
Notes payable, effective interest rate	0.00%			5.19%
Debt Instrument, Maturity Date	May 01, 2019
Secured Notes 5.33% Fixed Rate Mortgage Note Due 2019 [Member] \| Secured Debt [Member]
Secured notes payable				$ 19,400,000
Notes payable, effective interest rate	0.00%			5.33%
Debt Instrument, Maturity Date	Jun. 01, 2019
Minimum [Member] \| 2.70% Term loan Due 2022 \| Unsecured Debt [Member]
Notes payable, effective interest rate	2.70%
Unsecured Credit Facility [Member] \| Commercial Banks [Member]
Unsecured Debt	$ 44,000,000.0			$ 0