Derivative Instruments and Hedging Activities (Details) - Cash Flow Hedges (Cash Flow Hedging, USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Cash Flow Hedging
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gross notional amount outstanding	$ 650,000	$ 0
Derivative asset fair value	1,166	0
Derivative liability fair value	$ (3,096)	$ 0
Weighted-average interest rate received	1.63%	0.00%
Weighted-average interest rate paid	0.16%	0.00%
Weighted-average maturity (in years)	4 years 6 months 8 days	0 years

Derivative, Weighted Average Interest Rate Paid

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- Definition

Derivative, Weighted Average Interest Rate Received

+ References

No definition available.

+ Details

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- Definition

Derivative, Weighted Average Maturity

+ References

No definition available.

+ Details

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- Definition

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

+ References

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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- Definition

Fair value as of the balance sheet date of interest rate derivative assets, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as assets.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 10

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=35750535&loc=d3e13433-108611

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- Definition

Fair value as of the balance sheet date of interest rate derivative liabilities, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as liabilities.

+ References

+ Details

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