Amount of increase (decrease) in cash. Cash is the amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Includes effect from exchange rate changes.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 830

-SubTopic 230

-Section 45

-Paragraph 1

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

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- Definition

Description of the frequency of periodic payments (monthly, quarterly, annual).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Reference 3: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

-Topic 942

-SubTopic 470

-Section 50

-Paragraph 3

-Subparagraph (c)

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- Definition

The average effective interest rate during the reporting period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

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-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

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-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

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- Definition

Description of the interest rate as being fixed or variable, and, if variable, identification of the index or rate on which the interest rate is based and the number of points or percentage added to that index or rate to set the rate, and other pertinent information, such as frequency of rate resets.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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

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-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

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- Definition

Amount of debt issuance costs (for example, but not limited to, legal, accounting, broker, and regulatory fees).

+ References

No definition available.

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Balance Type:	credit
Period Type:	instant

- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

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- Definition

The interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a rate subject to change from time to time.

+ References

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- Definition

The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 15

-Subparagraph (b)

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-Glossary Financing Activities

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Debt - 2015 Credit Agreement (Details Textual) (USD $)	12 Months Ended			1 Months Ended
Debt - 2015 Credit Agreement (Details Textual) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Feb. 27, 2015
Debt Instrument [Line Items]
Cash used for repayment of debt	$ 15,000,000us-gaap_RepaymentsOfLongTermDebt	$ 15,000,000us-gaap_RepaymentsOfLongTermDebt	$ 190,000,000us-gaap_RepaymentsOfLongTermDebt
2015 Credit Agreement \| Revolving Loan
Debt Instrument [Line Items]
Credit Agreement	100,000,000
Subsequent Event
Debt Instrument [Line Items]
Debt instrument, frequency of periodic payment				payable quarterly
Debt instrument, interest rate terms				The 2015 Credit Agreement includes mandatory repayments of the aggregate principal amount of the 2015 Term Loan (payable quarterly) for the first (5% of total), second (5% of total), third (10% of total), fourth (15% of total), and fifth years (15% of total), with the remaining principal balance due at maturity (50% of total). The 2015 Credit Agreement has no prepayment penalties and requires mandatory repayments under certain circumstances, including: (i) asset sales or casualty proceeds; and (ii) proceeds of debt or preferred stock issuances.
Subsequent Event \| 2015 Credit Agreement
Debt Instrument [Line Items]
Credit Agreement				350,000,000
Cash used for repayment of debt				120,000,000
Increase (decrease) in available cash				30,000,000
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage				0.25%
Credit agreement interest rate				1.97%
Term loan combined interest rate				1.75%
Financing cost				2,400,000
Subsequent Event \| 2015 Credit Agreement \| Minimum
Debt Instrument [Line Items]
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage				0.25%
Subsequent Event \| 2015 Credit Agreement \| Maximum
Debt Instrument [Line Items]
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage				0.375%
Subsequent Event \| 2015 Credit Agreement \| London Interbank Offered Rate (LIBOR) \| Minimum
Debt Instrument [Line Items]
Basis spread on term loan				1.75%
Subsequent Event \| 2015 Credit Agreement \| London Interbank Offered Rate (LIBOR) \| Maximum
Debt Instrument [Line Items]
Basis spread on term loan				2.75%
Subsequent Event \| 2015 Credit Agreement \| Base Rate \| Minimum
Debt Instrument [Line Items]
Basis spread on term loan				0.75%
Subsequent Event \| 2015 Credit Agreement \| Base Rate \| Maximum
Debt Instrument [Line Items]
Basis spread on term loan				1.75%
Subsequent Event \| 2015 Credit Agreement \| Term Loan
Debt Instrument [Line Items]
Credit Agreement				150,000,000
Subsequent Event \| 2015 Credit Agreement \| Revolving Loan
Debt Instrument [Line Items]
Credit Agreement				200,000,000