Shareholders' Equity - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	Aug. 28, 2017	Jan. 26, 2017	Jun. 30, 2018	Jun. 30, 2017
Equity [Abstract]
Preferred stock shares authorized to issue			1,000,000	1,000,000
Preferred stock shares par value (in dollars per share)			$ 0.01	$ 0.01
Common stock, par value (in dollars per share)		$ 0.01	$ 0.01	$ 0.01
Shares sold (in shares)	200,000.0	6,900,000
Price of stock sold (in dollars per share)		$ 33.00
Consideration received on transaction		$ 215,725

Face amount or stated value per share of common stock.

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(29))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- References

No definition available.

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- Definition

Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.

+ 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(28))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws.

+ 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(28))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Cash received on stock transaction after deduction of issuance costs.

+ References

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

+ References

No definition available.

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- Definition

Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

+ References

No definition available.

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