Derivatives and Hedging (Narrative) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2008
Derivative Instruments, Gain (Loss) Reclassification from Accumulated OCI to Income, Estimated Net Amount to be Transferred	$ 0.8
Cash-flow hedges notional amount		120.0
Aggregate notional value of foreign exchange forward and swap arrangements	204.0	295.4
Fair values included in other assets	5.6	0.7
Fair values included in other liabilities	0.8	5.1
Variable rate debt qualifying for hedge accounting			200.0
Interest rate fair value hedge derivative at fair value recorded in accrued and other liabilities		2.7
Mature in 2010 [Member]
Aggregate fair value of interest rate swap		100.0
Mature in October 2011 [Member]
Aggregate fair value of interest rate swap	100.0
QIAGEN Finance [Member]
Aggregate notional amount foreign currency	44.0
Fair market value of foreign currency forward contracts		3.9
Fair market values of cash-flow hedges		3.9
QIAGEN Euro Finance [Member]
Fair market value of foreign currency forward contracts		4.6
Cash-flow hedges notional amount	120.0
Cash Flow Hedge Derivative Instrument Assets at Fair Value	0.7
Cash Flow Hedge Derivative Instrument Liabilities at Fair Value	1.7
Fair market values of cash-flow hedges		$ 4.6

Interest Rate Cash Flow Hedge Liability at Fair Value Current

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- Definition

Portion of company variable rate debt qualifying for Hedge Accounting.

+ References

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- Definition

Fair value of all asset derivatives designated as cash flow hedging instruments.

+ References

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 107

-Paragraph 10

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Fair value of all liability derivatives designated as cash flow hedging instruments.

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The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

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Fair value as of the balance sheet date of all foreign currency derivative liabilities designated as cash flow hedging instruments.

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Fair value as of the balance sheet date of all foreign currency derivative assets not designated as hedging instruments.

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Fair value as of the balance sheet date of all foreign currency derivative liabilities not designated as hedging instruments.

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Fair value of all derivatives designated as interest rate fair value hedging instruments.

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Aggregate notional amount of all foreign currency derivatives designated as hedging instruments in cash flow hedges. Notional amount refers to the number of currency units specified in the foreign currency derivative contract.

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Aggregate notional amount of all foreign currency derivatives not designated as hedging instruments. Notional amount refers to the number of currency units specified in the foreign currency derivative contract.

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Aggregate notional amount of foreign currency exchange rate derivatives. Notional amount refers to the number of currency units specified in the foreign currency derivative contract.

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