Derivative Financial Instruments (Narrative) (Details) (USD $) In Thousands, unless otherwise specified	0 Months Ended
Aug. 09, 2013	Mar. 31, 2015
2014 Swap [Member]
Derivative Financial Instruments [Line Items]
Notional amount		$ 107,234
Swap agreement collateral		29,989
2013 Swap [Member]
Derivative Financial Instruments [Line Items]
Notional amount		154,454
Swap agreement collateral		$ 39,999
Term of swap agreement	3 years
LIBOR [Member] \| 2014 Swap [Member]
Derivative Financial Instruments [Line Items]
Basis spread on variable rate		1.35%
LIBOR [Member] \| 2013 Swap [Member]
Derivative Financial Instruments [Line Items]
Basis spread on variable rate		1.20%

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

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- Details

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- Definition

The percentage points added to the reference rate to compute the variable rate on the interest rate derivative.

+ References

No definition available.

+ Details

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- Definition

Amount of right to receive securities collateral under master netting arrangements that have not been offset against derivative liabilities.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 20

-Section 55

-Paragraph 13

-URI http://asc.fasb.org/extlink&oid=28370219&loc=SL20226016-175313

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 20

-Section 50

-Paragraph 3

-Subparagraph (d)(2)

-URI http://asc.fasb.org/extlink&oid=20225523&loc=SL20225862-175312

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- Definition

Period the derivative contract is outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Details

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- Details

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