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Equity Incentive Compensation Plans and Other Long-term Incentive Programs - Narrative (Details) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2019 USD ($) unit $ / shares age shares	Dec. 31, 2018 USD ($) integer shares	Dec. 31, 2017 USD ($) shares	Dec. 31, 2015 unit	Dec. 31, 2014 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise of common stock options (in shares) \| shares	0	0	0
Unrecognized compensation cost \| $	$ 5,900
Weighted-average period (years)	1 year 7 months 6 days
Non-cash stock based compensation \| $	$ 8,622	$ 7,226	$ 8,289
Minimum age for employees to be eligible under employee directed savings plan \| age	21
Percentage of employee's contribution matched by the company	100.00%
Percentage of employee's pretax income	6.00%
Cash and common stock contributions \| $	$ 1,300	$ 1,200	$ 1,000
Percentage of employee's cash compensation reached under cash matching contributions	6.00%
2012 Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized \| shares	6,500,000
Number of shares available for grant \| shares	2,296,367
2016 Performance Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Plan Modification, Number of Employees Affected \| integer		23
Share-based Compensation Arrangement by Share-based Payment Award, Plan Modification, Incremental Compensation Cost \| $		$ 0
Adjustments to Additional Paid in Capital, Other \| $		$ 1,800
Percentage Of Original Award Converted To Nonvested Common Stock Award		89.00%
Number Of Units Converted To Nonvested Common Stock \| integer		592,472
Number Of Shares, Converted From Performance Cash Units \| shares		527,299
Number Of Units Not Converted To Nonvested Common Stock \| integer		65,173
2015 Performance Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted percentage of stockholders return related to performance goals	60.00%
Performance goals percentage for change in discretionary cash flows	40.00%
Vested, Shares \| shares		286,652
Percent of Performance Based Shares Vested		104.10%
Maximum Number Of Cash Units Vest As Percentage Of Performance Cash Units Granted	200.00%
Number Of Performance Cash Units Granted \| unit				422,345
2015 Performance Program \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of performance-based awards allowed to vest within a year	25.00%
2015 Performance Program \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of total grant that will vest for metrics met at stretch level	200.00%
Percentage of total grant that will vest for metrics met at target level	100.00%
Percentage of performance-based awards allowed to vest within a year	50.00%
2014 Performance Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted percentage of stockholders return related to performance goals	60.00%
Performance goals percentage for change in discretionary cash flows	40.00%
Vested, Shares \| shares			166,023
Percent of Performance Based Shares Vested			106.70%
2014 Performance Program \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of total grant that will vest for metrics met at stretch level	200.00%
Percentage of total grant that will vest for metrics met at target level	100.00%
Percentage of performance-based awards allowed to vest within a year	25.00%
2019 Performance Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Closing Share Price, December 31, 2018 \| $ / shares	$ 2.49
Absolute Performance Is Less Than 50%	50.00%
Payout Is Zero If Absolute Performance Is Less Than 50%	0.00%
Absolute Performance Is 50%	50.00%
Payout Is 50% If Absolute Performance Is 50%	50.00%
Absolute Performance Is 100%	100.00%
Payout Is 100% If Absolute Performance Is 100%	100.00%
Relative TSR Is Less Than 30%	30.00%
Payout Is Zero If Relative TSR Is Less Than 30%	0.00%
Relative TSR Is 30% Or Greater	30.00%
Payout Is Equal To Percentile Rank, Up To 100%, If Relative TSR Is Greater Than 30%	100.00%
2018 Performance Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Closing Share Price, December 29, 2017 \| $ / shares	$ 5.13
Payout If Share Price Less Than $5.13 \| unit	0
One Percent Vest For Each One Percent Growth	1.00%
Payout If Relative TSR Is Less Than Median \| unit	0
2017 Performance Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Plan Modification, Number of Employees Affected \| integer		34
Share-based Compensation Arrangement by Share-based Payment Award, Plan Modification, Incremental Compensation Cost \| $		$ 500
Adjustments to Additional Paid in Capital, Other \| $		$ 900
Percentage Of Original Award Converted To Nonvested Common Stock Award		100.00%
Number Of Units Converted To Nonvested Common Stock \| integer		619,006
Number Of Shares, Converted From Performance Cash Units \| shares		619,006
Nonvested Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Requisite service period	3 years
Fair value of performance-based shares vested in year \| $	$ (4,100)	$ (3,700)	$ (2,900)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period \| shares	1,847,700	1,185,809	791,129
Non-cash stock based compensation \| $	$ 6,601	$ 6,036	$ 5,852
Vested, Shares \| shares	1,696,963	694,505	513,376
Nonvested Equity Common Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Requisite service period	1 year
Non-cash stock based compensation \| $	$ 1,177	$ 1,138	$ 690
Nonvested Performance Cash Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Deferred Compensation Cash-based Arrangements, Liability, Current \| $			1,400
Deferred Compensation Cash-based Arrangements, Liability, Classified, Noncurrent \| $	$ 1,200	$ 300	$ 3,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period \| shares	2,026,521	935,293	669,043
Vested, Shares \| shares	0	286,652	0
Fair Value Performance Based Cash Unit Awards Vested \| $	$ 0	$ 1,500	$ 0
Nonvested Performance-Based Equity
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of performance-based shares vested in year \| $	$ 0	$ 0	$ (600)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period \| shares	0	0	0
Non-cash stock based compensation \| $	$ 0	$ 0	$ 558
Vested, Shares \| shares	0	0	166,023
Nonvested Performance-Based Equity \| 2014 Performance Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period \| shares					315,661
Absolute Performance \| 2018 Performance Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	150.00%
Relative TSR \| 2018 Performance Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	50.00%
Absolute Performance and Relative TSR \| 2019 Performance Program \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	200.00%
Absolute Performance and Relative TSR \| 2018 Performance Program \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	200.00%
Director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of performance-based shares vested in year \| $	$ (300)	$ (1,100)	$ (200)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period \| shares	643,084	226,244	193,878
Vested, Shares \| shares	158,218	187,566	68,486