Agreements and Transactions with Related Parties - Selling Commissions, Dealer Manager Fees and Shareholder Servicing Fees (Details) - $ / shares	Jun. 30, 2017	Apr. 27, 2017
CCIF \| Minimum
Reimbursed costs from affiliates and wholesaling revenue
Selling commission per share sold, percentage	0.00%
Dealer manager fee per share fee, percentage	2.50%
CCIF \| Maximum
Reimbursed costs from affiliates and wholesaling revenue
Selling commission per share sold, percentage	3.00%
Dealer manager fee per share fee, percentage	3.00%
CESH I \| Maximum \| Gross Offering Proceeds
Reimbursed costs from affiliates and wholesaling revenue
Selling commission per share sold, percentage	7.00%
Dealer manager fee per share fee, percentage	3.00%
CCIF 2016T
Reimbursed costs from affiliates and wholesaling revenue
Shareholder servicing, percentage	0.90%
Class A \| CWI 2
Reimbursed costs from affiliates and wholesaling revenue
Selling commission per share sold	$ 0.70	$ 0.84
Dealer manager fee per share sold	$ 0.30	0.36
Class C \| CPA:18 - Global
Reimbursed costs from affiliates and wholesaling revenue
Shareholder servicing, percentage	1.00%
Underwriting compensation limit, percentage	10.00%
Class T \| CWI 2
Reimbursed costs from affiliates and wholesaling revenue
Selling commission per share sold	$ 0.19	0.23
Dealer manager fee per share sold	$ 0.26	$ 0.31
Shareholder servicing, percentage	1.00%
Underwriting compensation limit, percentage	10.00%

Represents the per share dealer manager fee paid in connection with sale of common stock.

No definition available.

Name:	wpc_DealerManagerFeePerShareSold
Namespace Prefix:	wpc_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Represents the percentage of manager fee paid in connection with sale of common stock based on the selling price of the shares sold.

+ References

No definition available.

+ Details

Name:	wpc_DealerManagerFeePerShareSoldPercent
Namespace Prefix:	wpc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Reimbursed Costs From Affiliates And Wholesaling Revenue [Abstract]

+ References

No definition available.

+ Details

Name:	wpc_ReimbursedCostsFromAffiliatesAndWholesalingRevenueAbstract
Namespace Prefix:	wpc_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the per share commission rate paid in connection with the sale of common stock.

+ References

No definition available.

+ Details

Name:	wpc_SellingCommissionPerShareSold
Namespace Prefix:	wpc_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Represents the percentage of selling commission fee paid in connection with sale of common stock based on the selling price of the shares sold.

+ References

No definition available.

+ Details

Name:	wpc_SellingCommissionPerShareSoldPercentage
Namespace Prefix:	wpc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The percentage due to the dealer manager based on the sale of Class C Shares.

+ References

No definition available.

+ Details

Name:	wpc_ShareholderServicingFee
Namespace Prefix:	wpc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The percentage of gross offering proceeds related to the limit on underwriting compensation prescribed by Financial Industry Regulatory Authority, Inc.

+ References

No definition available.

+ Details

Name:	wpc_UnderwritingCompensationLimit
Namespace Prefix:	wpc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Details

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- Details

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- Details

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- Details

Name:	us-gaap_RelatedPartyTransactionAxis=wpc_CareyEuropeanStudentHousingFundIL.P.Member
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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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