Maximum aggregate offering price of common shares under the at-the-market share offering program.

No definition available.

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- Definition

Maximum aggregate offering price of common shares under the at-the-market share offering program available for sale.

+ References

No definition available.

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- Definition

The maximum number of common shares and nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws.

+ References

No definition available.

+ Details

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- Definition

The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

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- Definition

Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

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-Publisher FASB

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- Definition

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

+ References

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- Definition

The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws.

+ References

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

-Publisher FASB

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-SubTopic 10

-Section S99

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-Subparagraph (SX 210.5-02.28)

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-Name Regulation S-X (SX)

-Number 210

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- Definition

Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased.

+ References

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

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-SubTopic 10

-Section S99

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- Definition

Number of new stock issued during the period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

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Common Shares (Narrative) (Details) (USD $) In Millions, except Share data, unless otherwise specified	1 Months Ended	3 Months Ended		1 Months Ended
	Nov. 30, 2014	Mar. 31, 2015	Mar. 31, 2014	May 01, 2015	Dec. 31, 2014
Number of common and preferred stock authorized to issue		185,000,000cpt_SharesAuthorized
Common shares, authorized		175,000,000us-gaap_CommonStockSharesAuthorized			175,000,000us-gaap_CommonStockSharesAuthorized
Preferred shares, authorized		10,000,000us-gaap_PreferredStockSharesAuthorized
Common Stock, Shares, Outstanding		86,800,000us-gaap_CommonStockSharesOutstanding
Preferred Stock, Shares Outstanding		0us-gaap_PreferredStockSharesOutstanding
2014 ATM program [Member]
Maximum aggregate offering price of common shares	$ 331.3
Stock Issued During Period, Shares, New Issues		0.0	0.0
Subsequent Event [Member] \| 2014 ATM program [Member]
Stock Issued During Period, Shares, New Issues				0
Maximum aggregate offering price of remaining common shares available for sale				315.3
Line of Credit [Member]
Line of Credit Facility, Current Borrowing Capacity		500