Summary Of Significant Accounting Policies And Recent Accounting Pronouncements (Narrative) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]
Unamortized value of acquired in-place leases	$ 2.6	$ 0
Unamortized value of above or below market leases	0.7	0
Amortization of Intangible Assets	13.1	3.9	1.1
Amortization of above and below Market Leases	1.4	0	0
Capitalized interest	12.5	8.8	5.7
Capitalized real estate taxes	$ 2.8	$ 1.4	$ 0.8
Properties subject to rent control	9
Percentage Of Rental Revenue And Other Income From Leasing Of Apartment Homes	98.00%	98.00%	97.00%

The amount of real estate or property taxes that were capitalized during the period.

No definition available.

Name:	cpt_CapitalizedRealEstateTaxes
Namespace Prefix:	cpt_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Percentage of our total property revenues and total non-property income from leasing of apartment homes, excluding income on deferred compensation plans.

+ References

No definition available.

+ Details

Name:	cpt_PercentageOfRentalRevenueAndOtherIncomeFromLeasingOfApartmentHomes
Namespace Prefix:	cpt_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Properties subject to rent control as of the balance sheet date.

+ References

No definition available.

+ Details

Name:	cpt_PropertiesSubjectToRentControl
Namespace Prefix:	cpt_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Unamortized value of above or below market leases. This element represents the identifiable intangible asset established upon acquisition based on a favorable or unfavorable difference between the terms of an acquired lease and the current market terms for that lease at the acquisition date.

+ References

No definition available.

+ Details

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

- Definition

Amount of non-cash amortization of intangible asset (liability) for above and below market leases.

+ References

No definition available.

+ Details

Name:	us-gaap_AmortizationOfAboveAndBelowMarketLeases
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 142

-Paragraph 45

-Subparagraph a(2)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3602-108585

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16225-109274

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)(2)

-URI http://asc.fasb.org/extlink&oid=7658586&loc=d3e16323-109275

+ Details

Name:	us-gaap_AmortizationOfIntangibleAssets
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

This element represents the amount of value allocated by a lessor (acquirer) to lease agreements which exist at acquisition of a leased property. Such amount may include the value assigned to existing tenant relationships and excludes the market adjustment component of the value assigned for above or below-market leases acquired.

+ References

No definition available.

+ Details

Name:	us-gaap_FiniteLivedIntangibleAssetAcquiredInPlaceLeases
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of interest capitalized during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6450988&loc=d3e26243-108391

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Allowance for Funds Used during Construction

-URI http://asc.fasb.org/extlink&oid=6504829

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 34

-Paragraph 21

-Subparagraph b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration