The cash outflow to reacquire common stock during the period.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3291-108585

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- Definition

Expiration date for the purchase of an entity's own shares under a stock repurchase plan, in the CCYY-MM-DD format.

+ References

No definition available.

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- Definition

Amount remaining of a stock repurchase plan authorized.

+ References

No definition available.

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- Definition

Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21463-112644

Reference 2: 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 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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-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

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

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Subsequent Events - Additional Information (Detail) - USD ($)	2 Months Ended	12 Months Ended			44 Months Ended
	Mar. 26, 2020	Jan. 31, 2020	Jan. 31, 2019	Jan. 31, 2018	Jan. 31, 2020
Subsequent Event [Line Items]
Stock repurchased since the inception of repurchase programs, shares		0			3,985,876
Stock repurchased during period, cash		$ 0	$ 99,904,000	$ 54,788,000	$ 174,800,000
Amount available under stock repurchase program		$ 50,000,000.0			$ 50,000,000.0
Stock repurchase program, expiration date		Jun. 30, 2020
Subsequent Event [Member]
Subsequent Event [Line Items]
Stock repurchased since the inception of repurchase programs, shares	25,719
Stock repurchased during period, cash	$ 1,000,000.0
Amount available under stock repurchase program	$ 49,000,000.0
Stock repurchase program, expiration date	Jun. 30, 2020