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Stockholders' Equity - Additional Information (Details) - Common Stock - USD ($)
1 Months Ended 3 Months Ended
Mar. 31, 2018
Mar. 31, 2019
Mar. 31, 2018
Stockholders' Equity [Line Items]      
Stock repurchase program, authorized amount $ 200,000,000   $ 200,000,000
Stock repurchase program, duration 2 years    
Stock purchased and retired   900,000 0
Stock purchased and retired, amount   $ 20,000,000 $ 0