Income Taxes - Income Tax Expense (Benefit) Reconciliation (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Income Tax Disclosure [Abstract]
Tax at the federal statutory rate	$ 5,836	$ 976	$ 8,162	$ 5,144
State income taxes (net of federal benefit)	583	97	816	514
Tax effect of timber at the federal statutory rate of 23.8%	(112)	(54)	(226)	(260)
Decrease in valuation allowance	(316)	(9)	(596)	(363)
Other	(82)	(32)	32	(813)
Total income tax expense	$ 5,909	$ 978	$ 8,188	$ 4,222
Federal statutory rate			35.00%	35.00%
Timber statutory federal rate			23.80%	23.80%