Derivative Financial Instruments (Narrative) (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013
Derivative [Line Items]
Derivative, Total Notional Amount	$ 721,438
Interest Rate Swap [Member] \| Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative, Total Notional Amount	200,000
Cash Flow Hedging [Member] \| Interest Rate Swap [Member] \| Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative, Total Notional Amount	$ 521,438

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 12

-Section 13

-Sentence Column B

Name:	invest_DerivativeNotionalAmount
Namespace Prefix:	invest_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	instant