Stockholders' Equity - Schedule of Share Repurchase Activity under Share Repurchase Programs (Detail) $ / shares in Units, $ in Thousands	3 Months Ended
Mar. 31, 2019 USD ($) $ / shares shares
Equity [Abstract]
Number of common shares acquired \| shares	4,890,766
Average price per common share acquired \| $ / shares	$ 22.88
Total cost of common shares acquired \| $	$ 111,885

Equity impact of the value of stock that has been repurchased and retired during the period. The excess of the purchase price over par value can be charged against retained earnings (once the excess is fully allocated to additional paid in capital).

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Balance Type:	debit
Period Type:	duration