Derivative Financial Instruments (Executed interest rate Swap) (Details) (USD $) In Millions, unless otherwise specified	Apr. 20, 2011 Interest Rate Swap 1	Mar. 31, 2009 Interest Rate Swap
Derivative [Line Items]
Derivative, notional amount	$ 15.0	$ 65.0

Amount of the hedged item as of the balance sheet date related to the derivative. For example, the hedged balance on a debt instrument.

No definition available.

Name:	us-gaap_DerivativeAmountOfHedgedItem
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	instant