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

Under the terms of the advisory agreements, percentage of total performance fees that is receivable in cash.

No definition available.

Name:	wpc_AssetManagementFeesReceivableInCashPercentOfTotal
Namespace Prefix:	wpc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

Under the terms of the advisory agreements, percentage of total performance fees that is receivable in restricted shares.

No definition available.

Name:	wpc_AssetManagementFeesReceivableInSharesPercentOfTotal
Namespace Prefix:	wpc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

The percentage of fees paid to the advisor by its affiliates for the structuring and negotiating investments on the company's behalf and based on the aggregate total costs of an investment for all investments other than those in readily-marketable real estate securities purchased in the secondary market.

No definition available.

Name:	wpc_PercentageOfAcquisitionFeesEarned
Namespace Prefix:	wpc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

The maximum percentage of available cash generated from operations, excluding capital proceeds, as reduced by operating expenses and debt service, excluding prepayments and balloon payments, of the operating partnership that is paid to the advisor for service fees.

No definition available.

Name:	wpc_PercentageOfAvailableCashDistributionToAdvisor
Namespace Prefix:	wpc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

Percentage of fees related to certain personnel services under the advisory agreement that the advisor must pay to the subadvisor.

No definition available.

Name:	wpc_PercentageOfFeesEarnedByAdvisorPaidToSubadvisor
Namespace Prefix:	wpc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

The percentage that is used to caclulate the fee costs paid to the advisor for refinancing loans. The percentage is based on the amount of loan refinanced.

No definition available.

Name:	wpc_PercentageOfLoanRefinancingFee
Namespace Prefix:	wpc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

Percentage of Structuring Fees Paid in Cash

No definition available.

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

Percentage of Structuring Fees Paid in Shares

No definition available.

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

The percentage fee paid to the company by its affiliates for managing the company's assets based on the average market value or average equity value, as applicable, depending on the type of investments.

No definition available.

Name:	wpc_Percentageofassetmanagementfeesearned
Namespace Prefix:	wpc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

Structuring Revenue [Abstract]

No definition available.