Line of Credit Facility, Potential Additional Borrowing Capacity

No definition available.

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Namespace Prefix:	gk_
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- Definition

Line of Credit Facility Refinanced Borrowings

+ References

No definition available.

+ Details

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Namespace Prefix:	gk_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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

+ Details

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Period Type:	instant

- Definition

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

+ References

No definition available.

+ Details

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ 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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

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

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

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ 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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(2))

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

+ Details

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Period Type:	duration

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.16)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 20, 22

-Article 5

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.16)

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

+ Details

Name:	us-gaap_LineOfCredit
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

+ 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 210.5-02.19(b),22(b))

-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 19, 22

-Article 5

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Date the credit facility terminates, in CCYY-MM-DD format.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- 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.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The cash outflow to repay long-term debt that is not secured by collateral. Excludes repayments of tax exempt unsecured debt.

+ 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)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3291-108585

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

-URI http://asc.fasb.org/extlink&oid=6513228

+ Details

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Period Type:	duration

- Details

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- Details

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- Details

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- Details

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Subsequent Events (Details) (USD $)	3 Months Ended	9 Months Ended	0 Months Ended
Subsequent Events (Details) (USD $)	Jun. 27, 2015	Mar. 28, 2015	Apr. 15, 2025	Apr. 15, 2020	Mar. 07, 2017	Jun. 28, 2014	Apr. 15, 2015	Apr. 01, 2015
Subsequent Event [Line Items]
Long-term line of credit		25,900,000us-gaap_LineOfCredit				$ 65,925,000us-gaap_LineOfCredit
Subsequent event
Subsequent Event [Line Items]
Line of credit facility, Potential additional borrowing capacity	200,000
Revolving credit facility
Subsequent Event [Line Items]
Line of Credit Facility, Refinanced Borrowings		250,000,000
Long-term line of credit		25,900,000
Debt instrument, interest rate, effective percentage		1.56%
Revolving credit facility \| Subsequent event
Subsequent Event [Line Items]
Line of Credit Facility, Refinanced Borrowings							250,000,000
Line of credit facility, maximum borrowing capacity							550,000
Minimum \| Revolving credit facility
Subsequent Event [Line Items]
Interest rate spread on notes (in percent)		1.00%
Maximum \| Revolving credit facility
Subsequent Event [Line Items]
Interest rate spread on notes (in percent)		2.00%
Unsecured private placement notes
Subsequent Event [Line Items]
Debt instrument, interest rate, effective percentage		0.86%
Debt Instrument, maturity date		Jun. 30, 2015
Unsecured private placement notes \| Subsequent event
Subsequent Event [Line Items]
Repayments of unsecured debt			75,000,000
Interest rate swap
Subsequent Event [Line Items]
Derivative, notional amount		75,000,000
Interest rate swap \| Subsequent event
Subsequent Event [Line Items]
Debt instrument, interest rate, effective percentage								2.35%
Derivative, notional amount								75,000
London Interbank Offered Rate (LIBOR) \| Unsecured private placement notes
Subsequent Event [Line Items]
Interest rate spread on notes (in percent)		0.60%
Scenario, forecast \| Revolving credit facility
Subsequent Event [Line Items]
Line of credit facility, expiration date				Apr. 15, 2020	Mar. 07, 2017
Line of Credit Facility, Current Borrowing Capacity							350,000
Long-term line of credit							30,000,000
Debt instrument, interest rate, effective percentage							1.44%
Scenario, forecast \| Secured revolving credit facility
Subsequent Event [Line Items]
Line of credit facility, maximum borrowing capacity							$ 45,000
Scenario, forecast \| London Interbank Offered Rate (LIBOR) \| Minimum \| Revolving credit facility
Subsequent Event [Line Items]
Interest rate spread on notes (in percent)	1.00%
Scenario, forecast \| London Interbank Offered Rate (LIBOR) \| Maximum \| Revolving credit facility
Subsequent Event [Line Items]
Interest rate spread on notes (in percent)	1.75%