Revenue earned by providing property management, construction, development, and other services to joint ventures.

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Namespace Prefix:	cpt
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Number of apartment units in properties acquired during the period by our discretionary funds (unconsolidated joint ventures).

+ Details

Name:	cpt_NumberOfApartmentUnitsInPropertyAcquired
Namespace Prefix:	cpt
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of joint ventures accounted for under equity method investments.

+ Details

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Namespace Prefix:	cpt
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Number of multifamily properties acquired by our discretionary funds (unconsolidated joint ventures) during the period.

+ Details

Name:	cpt_NumberOfPropertiesAcquired
Namespace Prefix:	cpt
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

The cash inflow from the sale of a development property including reimbursement of previously written-off third-party development costs.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

This item represents the amount of net sales proceeds received on disposal of an equity method investment.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 35

-Paragraph 35

-URI http://asc.fasb.org/extlink&oid=6903645&loc=d3e32847-111569

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 159

-Paragraph 18

-Subparagraph f

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 18

-Paragraph 20

-Subparagraph a (1)

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571

+ Details

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- Definition

This item represents the amount of gain (loss) arising from the disposal of an equity method investment.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

The difference between the sale price or salvage price and the book value of a property, plant, and equipment asset that was sold or retired during the reporting period. This element refers to the gain (loss).

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 28

-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

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- Definition

Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

+ References

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

-Publisher FASB

-Name FASB Interpretation (FIN)

-Number 45

-Paragraph 13

-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.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 460

-SubTopic 10

-Section 50

-Paragraph 4

-Subparagraph (b)(1)

-URI http://asc.fasb.org/extlink&oid=6851643&loc=d3e12069-110248

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- Definition

The cash inflow from the sale of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 12

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3179-108585

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 15

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 16

-Subparagraph c

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

-URI http://asc.fasb.org/extlink&oid=6516133

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Investments In Joint Ventures (Narrative) (Details) (USD $)	1 Months Ended		3 Months Ended		9 Months Ended				1 Months Ended	9 Months Ended			1 Months Ended	9 Months Ended			1 Months Ended
	Nov. 04, 2011	Mar. 31, 2011	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011 Minimum [Member]	Sep. 30, 2011 Maximum [Member]	Nov. 04, 2011 Houston Texas [Member]	Sep. 30, 2011 Houston Texas [Member]	Sep. 30, 2011 Atlanta Georgia [Member]	Sep. 30, 2011 Tampa Florida [Member]	Jun. 30, 2011 Austin Texas [Member]	Sep. 30, 2011 Austin Texas [Member]	Sep. 30, 2011 San Antonio Texas [Member]	Sep. 30, 2011 Dallas Texas [Member]	Apr. 30, 2011 Washington, D.C. [Member]
Number of joint ventures accounted for under equity method investments			17		17
Equity method investment ownership percentage							15.00%	50.00%									20.00%
Maximum guaranteed amount of loans utilized for construction and development activities for joint ventures			$ 0		$ 0
Fees earned for property and asset management, construction, development, and other services to joint ventures			2,400,000	1,600,000	6,400,000	4,700,000
Proceeds from sale of ownership interests in three unconsolidated joint venture communities		19,300,000
Gain on sale of unconsolidated joint venture interests					(1,136,000)
Number of multifamily properties acquired by our discretionary funds	5				13
Number of units in multifamily properties acquired									1,488	1,358	234	450		768	528	1,250
Proceeds from sale of property													3,100,000
Proceeds from sale of development property with reimbursement																	9,400,000
Gain on sale of properties													$ 100,000				$ 4,700,000