Real Estate Real Estate (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
Real Estate [Abstract]
Properties in operation	$ 200,010,000wrb_BuildingandLeaseObligations	$ 196,980,000wrb_BuildingandLeaseObligations
Properties under development	561,846,000us-gaap_DevelopmentInProcess	534,632,000us-gaap_DevelopmentInProcess
Total	761,856,000us-gaap_RealEstateInvestmentPropertyNet	731,612,000us-gaap_RealEstateInvestmentPropertyNet
Real Estate Investment Property, Accumulated Depreciation	$ 4,113,000	$ 1,609,000

The current amount of expenditures for a real estate project that has not yet been completed.

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- Details

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- Definition

The cumulative amount of depreciation for real estate property held for investment purposes.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.1(3))

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Article 7

+ Details

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- Definition

Amount of real estate investment property, net of accumulated depreciation, which may include the following: (1) land available-for-sale; (2) land available-for-development; (3) investments in building and building improvements; (4) tenant allowances; (5) developments in-process; (6) rental properties; and (7) other real estate investments.

+ References

+ Details

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- Definition

Building and Lease Obligations

+ References

No definition available.

+ Details

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