Stock Incentive Plans - Stock Option Activity (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended	6 Months Ended
Mar. 31, 2020	Jun. 30, 2019	Dec. 31, 2019
Number Of Shares (in thousands)
Outstanding, beginning balance (in shares)	1,284
Options exercised (in shares)	(20)
Options forfeited/expired/canceled (in shares)	(18)
Options granted (in shares)	0
Outstanding, ending balance (in shares)	1,246
Exercisable, end of period (in shares)	1,073
Vested and expected to vest, end of period (in shares)	1,234
Weighted Average Exercise Price
Outstanding, beginning balance (in usd per share)	$ 22.66
Options exercised (in usd per share)	19.23
Options forfeited/expired/canceled (in usd per share)	28.39
Options granted (in usd per share)	0
Outstanding, ending balance (in usd per share)	22.62
Exercisable, end of period (in usd per share)	21.87
Vested and expected to vest, end of period (in usd per share)	$ 22.58
Other Disclosures
Outstanding, weighted-average remaining contractual term	3 years 7 days	3 years 2 months 4 days
Exercisable, weighted-average remaining contractual term	2 years 7 months 2 days
Vested and expected to vest, weighted-average remaining contractual term	3 years
Outstanding, aggregated intrinsic value	$ 249		$ 3,171
Exercisable, aggregated intrinsic value	249
Vested and expected to vest, aggregated intrinsic value	$ 249

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Number of options outstanding, including both vested and non-vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Number of fully vested and expected to vest options outstanding that can be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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