Summary of Significant Accounting Policies Derivative (Details) (Cash Flow Hedging [Member], Interest Rate Swap [Member], USD $) In Millions, unless otherwise specified	Mar. 31, 2015
Cash Flow Hedging [Member] \| Interest Rate Swap [Member]
Derivative [Line Items]
Derivative, amount of hedged items	$ 300.0

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