Subsequent Event - Additional Information (Detail) (Subsequent Event, USD $) In Thousands, unless otherwise specified	1 Months Ended
Jul. 01, 2013
Subsequent Event [Line Items]
Revolving credit agreement maximum borrowing capacity	$ 500,000
Minimum
Subsequent Event [Line Items]
Commitment fee percentage on unused portion of the commitment	12.50%
Maximum
Subsequent Event [Line Items]
Commitment fee percentage on unused portion of the commitment	35.00%
Before Extension
Subsequent Event [Line Items]
Revolving credit agreement maturity date	Apr. 27, 2017
After Extension
Subsequent Event [Line Items]
Revolving credit agreement maturity date	Jul. 01, 2018
Scenario 1 \| Minimum
Subsequent Event [Line Items]
Basis spread	87.50%
Scenario 1 \| Maximum
Subsequent Event [Line Items]
Basis spread	250.00%
Scenario 2 \| Minimum
Subsequent Event [Line Items]
Basis spread	0.00%
Scenario 2 \| Maximum
Subsequent Event [Line Items]
Basis spread	150.00%

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

No definition available.

Name:	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

+ References

No definition available.

+ Details

Name:	us-gaap_LineOfCreditFacilityCommitmentFeePercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

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

+ 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

Name:	us-gaap_LineOfCreditFacilityExpirationDate1
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

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

- Details

Name:	us-gaap_SubsequentEventLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration