No definition available.

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- Definition

Aggregate dividends paid during the period for each share of common stock outstanding.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
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- Definition

Date the declared dividend will be paid, in CCYY-MM-DD format.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
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- Definition

Date the dividend to be paid was declared, in CCYY-MM-DD format.

+ References

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- Definition

Date the holder must own the stock to be entitled to the dividend, in CCYY-MM-DD format.

+ References

No definition available.

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- Definition

Amount of cash outflow in the form of ordinary dividends to common shareholders of the parent entity.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (a)
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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.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
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- References

No definition available.

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- Definition

Total cost of shares repurchased divided by the total number of shares repurchased.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 30
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Reconciliation of Weighted Average Shares Outstanding and Share Repurchases, Share Repurchases and Dividends (Details) - USD ($) $ / shares in Units, $ in Thousands							3 Months Ended		9 Months Ended
	Jan. 16, 2019	Dec. 19, 2018	Oct. 24, 2018	Sep. 26, 2018	Jul. 18, 2018	Jun. 21, 2018	Jan. 31, 2019	Jan. 31, 2018	Jan. 31, 2019	Jan. 31, 2018
Cash dividend [Abstract]
Cash dividends	$ 18,900		$ 18,900		$ 19,000				$ 56,963	$ 55,093
Class A Common [Member]
Share repurchases [Abstract]
Shares repurchased (in shares)							208,711	0	633,831	550,757
Average purchase price (in dollars per share)							$ 47.91	$ 0	$ 55.21	$ 53.12
Cash dividend [Abstract]
Common stock (in dollars per share)							0.33	0.32	$ 0.99	0.96
Class A Common [Member] \| Dividend Declared in Q1 2019 [Member]
Cash dividend [Abstract]
Dividend declared date									Jun. 21, 2018
Common stock (in dollars per share)						$ 0.33
Dividend payable date									Jul. 18, 2018
Dividend record date									Jul. 03, 2018
Class A Common [Member] \| Dividend Declared in Q2 2019 [Member]
Cash dividend [Abstract]
Dividend declared date									Sep. 26, 2018
Common stock (in dollars per share)				$ 0.33
Dividend payable date									Oct. 24, 2018
Dividend record date									Oct. 09, 2018
Class A Common [Member] \| Dividend Declared in Q3 2019 [Member]
Cash dividend [Abstract]
Dividend declared date									Dec. 19, 2018
Common stock (in dollars per share)		$ 0.33
Dividend payable date									Jan. 16, 2019
Dividend record date									Jan. 02, 2019
Class B Common [Member]
Cash dividend [Abstract]
Common stock (in dollars per share)							$ 0.33	$ 0.32	$ 0.99	$ 0.96
Class B Common [Member] \| Dividend Declared in Q1 2019 [Member]
Cash dividend [Abstract]
Dividend declared date									Jun. 21, 2018
Common stock (in dollars per share)						$ 0.33
Dividend payable date									Jul. 18, 2018
Dividend record date									Jul. 03, 2018
Class B Common [Member] \| Dividend Declared in Q2 2019 [Member]
Cash dividend [Abstract]
Dividend declared date									Sep. 26, 2018
Common stock (in dollars per share)				$ 0.33
Dividend payable date									Oct. 24, 2018
Dividend record date									Oct. 09, 2018
Class B Common [Member] \| Dividend Declared in Q3 2019 [Member]
Cash dividend [Abstract]
Dividend declared date									Dec. 19, 2018
Common stock (in dollars per share)		$ 0.33
Dividend payable date									Jan. 16, 2019
Dividend record date									Jan. 02, 2019