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

Reference 1: 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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Date the declared dividend will be paid, in CCYY-MM-DD format.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4304-108586

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

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

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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.

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Subsequent Events - Additional Information (Narrative) (Details) - Subsequent Event [Member] - $ / shares	May 24, 2019	May 10, 2019	Apr. 26, 2019
Subsequent Events [Line Items]
Date of announcement of dividend			Apr. 26, 2019
Date of payment of dividend	May 24, 2019
Date of record of dividend		May 10, 2019
Class A Stock
Subsequent Events [Line Items]
Quarterly dividend payable amount per share			$ 0.11
Class B Stock
Subsequent Events [Line Items]
Quarterly dividend payable amount per share			$ 0.11