Debt Instrument, Annual Fixed Coupon Rate

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- Definition

Debt Instrument, Covenant, Interest Coverage Ratio

+ References

No definition available.

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- Definition

Debt Instrument, Covenant, Maximum Ratio of Consolidated Net Indebtedness to Total Assets

+ References

No definition available.

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- Definition

Debt Instrument, Covenant, Maximum Ratio of Consolidated Secured Indebtedness to Total Assets

+ References

No definition available.

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- Definition

Debt Instrument, Covenant, Maximum Ratio of Unencumbered Assets to Unsecured Indebtedness

+ References

No definition available.

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- Definition

Debt Instrument, Swap Arrangements, Percentage of Proceeds Converted

+ References

No definition available.

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- Definition

Long-term Debt, Net of Premium (Discount)

+ References

No definition available.

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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- Definition

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

+ References

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- 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.

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- 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

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- Definition

Amount after tax, before reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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- Definition

The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

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KWE Unsecured Bonds - Additional Information (Details) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018 USD ($)	Jun. 30, 2017 USD ($)	Jun. 30, 2018 USD ($)	Jun. 30, 2018 EUR (€)	Jun. 30, 2017 USD ($)	Jun. 30, 2018 GBP (£)	Dec. 31, 2017 USD ($)
Debt Instrument [Line Items]
Effective interest rate	3.831%		3.831%			3.831%
Unrealized foreign currency translation loss	$ 74.3	$ (99.6)	$ 38.9		$ (120.8)
KWE [Member] \| United Kingdom, Pounds [Member]
Debt Instrument [Line Items]
Unrealized foreign currency translation loss			2.4
Unsecured Bonds [Member]
Debt Instrument [Line Items]
Long-term debt	$ 1,295.0		$ 1,295.0				$ 1,325.9
Unsecured Bonds [Member] \| United Kingdom [Member] \| Mortgage Loans, Unsecured [Member]
Debt Instrument [Line Items]
Maximum percentage of total assets	60.00%		60.00%			60.00%
Maximum ratio of consolidated secured indebtedness to total assets	50.00%		50.00%			50.00%
Interest coverage ratio	1.50		1.50			1.50
Maximum ratio of unencumbered assets to unsecured indebtedness	125.00%		125.00%			125.00%
Unsecured Bonds [Member] \| KWE [Member]
Debt Instrument [Line Items]
Mortgage debt (excluding loan fees)	$ 1,299.9		$ 1,299.9				1,331.3
Long-term debt	1,295.0		1,295.0				1,325.9
Unsecured Bonds [Member] \| KWE [Member] \| KWE Euro Medium Term Note Programme [Member]
Debt Instrument [Line Items]
Mortgage debt (excluding loan fees)	$ 639.7		$ 639.7				655.7
Unsecured Bonds [Member] \| KWE [Member] \| United Kingdom [Member] \| KWE Bonds [Member]
Debt Instrument [Line Items]
Debt face value \| £						£ 500,000,000
Interest rate (as a percent)	3.95%		3.95%			3.95%
Mortgage debt (excluding loan fees)	$ 660.2		$ 660.2				$ 675.6
Unsecured Bonds [Member] \| KWE [Member] \| United Kingdom [Member] \| KWE Euro Medium Term Note Programme [Member]
Debt Instrument [Line Items]
Debt face value	$ 2,600.0		2,600.0			£ 2,000,000,000.0
Proceeds from issuance of debt			$ 642.6	€ 550,000,000
Annual fixed coupon rate	3.25%		3.25%			3.25%
Unsecured Bonds [Member] \| KWE [Member] \| United Kingdom [Member] \| Mortgage Loans, Unsecured [Member]
Debt Instrument [Line Items]
Effective interest rate	3.35%		3.35%			3.35%
Percentage of proceeds converted to Euros with swaps			50.00%	50.00%