Stockholders' Equity (Details) - Common Stock - USD ($) shares in Millions, $ in Millions	22 Months Ended
Mar. 31, 2019	Jun. 30, 2017
Stockholders' Equity
Authorized stock repurchase amount		$ 50
Shares of common stock repurchased	13.9

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-Name Accounting Standards Codification
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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration