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

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Contractual interest rate for funds borrowed, under the debt agreement.

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

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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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Subsequent Events - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions	Feb. 11, 2019	Feb. 05, 2019	Dec. 31, 2018	Nov. 06, 2018
6.125% Senior Notes Due 2023 [Member]
Subsequent Event [Line Items]
Stated interest rate		6.125%	6.125%	6.125%
Subsequent Event [Member]
Subsequent Event [Line Items]
Common stock dividends per share declared	$ 0.09
Dividend payable date	Mar. 13, 2019
Dividends payable date declared	Feb. 11, 2019
Dividends payable date of record	Feb. 28, 2019
Subsequent Event [Member] \| 6.125% Senior Notes Due 2023 [Member] \| Maximum [Member]
Subsequent Event [Line Items]
Debt Instrument, Exchange Amount		$ 550