Notes Payable - Terms of Notes Payable (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Notes payable, gross	$ 2,049,680	$ 2,160,293
Unamortized premium	4,826	7,574
Unamortized loan costs	(6,907)	(5,148)
Total Notes Payable	$ 2,047,599	2,162,719
Weighted average maturity of notes payable	4 years 4 months 20 days
Unsecured Notes
Debt Instrument [Line Items]
Notes payable, gross	$ 1,384,000	1,482,400
Credit Facility, Unsecured
Debt Instrument [Line Items]
Interest Rate	1.13%
Notes payable, gross	$ 34,000	232,400
Term Loan, Unsecured
Debt Instrument [Line Items]
Interest Rate	1.13%
Notes payable, gross	$ 350,000	$ 0
Term Loan, Unsecured
Debt Instrument [Line Items]
Interest Rate		1.30%
Notes payable, gross	$ 0	$ 250,000
Senior Notes, Unsecured \| 2019 Senior Notes, Unsecured
Debt Instrument [Line Items]
Interest Rate	3.95%
Notes payable, gross	$ 275,000	275,000
Senior Notes, Unsecured \| 2017 Senior Notes, Unsecured
Debt Instrument [Line Items]
Interest Rate	3.91%
Notes payable, gross	$ 250,000	250,000
Senior Notes, Unsecured \| 2019 Senior Notes, Unsecured
Debt Instrument [Line Items]
Interest Rate	3.86%
Notes payable, gross	$ 250,000	250,000
Senior Notes, Unsecured \| 2019 Senior Notes, Unsecured
Debt Instrument [Line Items]
Interest Rate	3.78%
Notes payable, gross	$ 125,000	125,000
Senior Notes, Unsecured \| 2017 Senior Notes, Unsecured
Debt Instrument [Line Items]
Interest Rate	4.09%
Notes payable, gross	$ 100,000	100,000
Secured Mortgage Notes
Debt Instrument [Line Items]
Notes payable, gross	$ 665,680	677,893
Secured Mortgage Notes \| Fifth Third Center
Debt Instrument [Line Items]
Interest Rate	3.37%
Notes payable, gross	$ 134,529	137,057
Secured Mortgage Notes \| Terminus 100
Debt Instrument [Line Items]
Interest Rate	5.25%
Notes payable, gross	$ 112,524	114,997
Secured Mortgage Notes \| Colorado Tower
Debt Instrument [Line Items]
Interest Rate	3.45%
Notes payable, gross	$ 112,786	114,660
Secured Mortgage Notes \| Promenade
Debt Instrument [Line Items]
Interest Rate	4.27%
Notes payable, gross	$ 89,952	92,593
Secured Mortgage Notes \| Domain 10
Debt Instrument [Line Items]
Interest Rate	3.75%
Notes payable, gross	$ 76,874	78,232
Secured Mortgage Notes \| Terminus 200
Debt Instrument [Line Items]
Interest Rate	3.79%
Notes payable, gross	$ 73,015	74,354
Secured Mortgage Notes \| Legacy Union One
Debt Instrument [Line Items]
Interest Rate	4.24%
Notes payable, gross	$ 66,000	$ 66,000

Debt Instrument, Weighted Average Maturity Period

No definition available.

Name:	cuz_DebtInstrumentWeightedAverageMaturityPeriod
Namespace Prefix:	cuz_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

+ Details

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

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1B
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-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=120391452&loc=d3e13212-122682

+ Details

Name:	us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount, after accumulated amortization, of debt premium.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1D
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495340-112611

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=124435984&loc=d3e28541-108399

+ Details

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

- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ 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
-Subparagraph (SX 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1D
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495340-112611

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=124435984&loc=d3e28555-108399

+ Details

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

- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)(3)
-URI http://asc.fasb.org/extlink&oid=123466204&loc=SL6031897-161870

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 55
-Paragraph 69C
-URI http://asc.fasb.org/extlink&oid=123466577&loc=SL123495737-112612

Reference 3: 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=120400017&loc=d3e572229-122910

Reference 4: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 55
-Paragraph 69B
-URI http://asc.fasb.org/extlink&oid=123466577&loc=SL123495735-112612

Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
-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=120398452&loc=d3e534808-122878

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1D
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495340-112611

Reference 7: http://fasb.org/us-gaap/role/ref/legacyRef
-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=120391452&loc=d3e13212-122682

+ Details

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