Stockholders' Equity - Additional Information (Detail) - $ / shares	1 Months Ended	3 Months Ended
Jul. 30, 2018	Jun. 30, 2018
Equity Class Of Treasury Stock [Line Items]
Repurchase of shares		500,300
Shares repurchased average price		$ 104.62
Subsequent Event [Member]
Equity Class Of Treasury Stock [Line Items]
Repurchase of shares	126,000
Shares repurchased average price	$ 106.93
Stock repurchase remaining number of shares authorized to be repurchased	3,563,128

Number of shares that have been repurchased and retired during the period.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-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

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21463-112644

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