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Stock Incentive Plan and Other Equity Activity (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Sep. 30, 2019	Sep. 30, 2018
Sale of Stock [Line Items]
Shares granted (in shares)							375
Shares issued (in shares)							192
Stock-based compensation expense	$ 819			$ 798			$ 2,489	$ 2,181
Purchase of treasury stock			$ 3,201
Shares withheld for taxes	$ 32	$ 98	$ 564	$ 7	$ 107	$ 194
Common Stock
Sale of Stock [Line Items]
Purchase of treasury stock (in shares)							250
Purchase of treasury stock							$ 3,201
Shares withheld for taxes (in shares)	3						62
Shares withheld for taxes	$ 32						$ 694
ESPP
Sale of Stock [Line Items]
Maximum annual contributions per employee (percent)							15.00%
Maximum annual amount of contributions per employee							$ 25
Discount from market price on purchase date (percent)							85.00%
RSAs
Sale of Stock [Line Items]
Shares granted (in shares)							52
Weighted Average Grant-Date Fair Value per Share (in dollars per share)							$ 12.06
Shares issued (in shares)							52
RSUs
Sale of Stock [Line Items]
Shares granted (in shares)							138
Weighted Average Grant-Date Fair Value per Share (in dollars per share)							$ 10.96
Shares issued (in shares)							80
PSUs
Sale of Stock [Line Items]
Shares granted (in shares)							185
Weighted Average Grant-Date Fair Value per Share (in dollars per share)							$ 10.89
Shares issued (in shares)							54
ESPP
Sale of Stock [Line Items]
Shares issued (in shares)							6
Stock-based compensation expense	$ 12						$ 12
Remaining authorized shares available for purchase (in shares)	794						794

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Share-based Compensation Arrangement by Share-based Payment Award, Maximum Annual Contributions Per Employee, Amount

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