Subsequent Events (Details) - Subsequent events $ / shares in Units, $ in Millions	Oct. 10, 2019 USD ($) $ / shares
Subsequent events
Cash dividend declared (in dollars per share) \| $ / shares	$ 0.28
Dividend payable \| $	$ 17.9

Carrying value as of the balance sheet date of dividends declared but unpaid on equity securities issued by the entity and outstanding.

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(24))
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant