Incentive Stock Plans - Summary of Stock Option Activity (Details) - Stock Options $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2019 USD ($) $ / shares shares
Options
Beginning balance (in shares) | shares	286,613
Forfeited (in shares) | shares	0
Exercised (in shares) | shares	0
Expired (in shares) | shares	(81,587)
Ending balance (in shares) | shares	205,026
Options vested and expected to vest (in shares) | shares	205,026
Options exercisable (in shares) | shares	205,026
Weighted Average Exercise Price
Beginning balance (in dollars per share) | $ / shares	$ 34.23
Forfeited (in dollars per share) | $ / shares	0
Exercised (in dollars per share) | $ / shares	0
Expired (in dollars per share) | $ / shares	29.54
Ending balance (in dollars per share) | $ / shares	36.10
Options vested and expected to vest (in dollars per share) | $ / shares	36.10
Options exercisable (in dollars per share) | $ / shares	$ 36.10
Additional Disclosures
Weighted Average Remaining Contractual Term, Outstanding	2 years 4 months 24 days
Weighted Average Remaining Contractual Term, Options vested and expected to vest	2 years 4 months 24 days
Weighted Average Remaining Contractual Term, Options exercisable	2 years 4 months 24 days
Aggregate Intrinsic Value, Outstanding | $	$ 0
Aggregate Intrinsic Value, Options vested and expected to vest | $	0
Aggregate Intrinsic Value, Options exercisable | $	$ 0