Income Taxes - Income Tax Provision (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Taxes
Statutory Rate (as a percent)									21.00%	21.00%	35.00%
Income tax expense related to the write-down of deferred tax assets											$ 2,005
Current Tax Provision									$ 7,670	$ 6,522	10,206
Deferred Tax Benefit									(747)	(1,298)	(2,062)
Change in Deferred Taxes Due to Enacted Changes in Tax Law											(2,005)
Total Income Tax Provision	$ 1,380	$ 2,092	$ 1,189	$ 2,262	$ (1,302)	$ 2,184	$ 2,274	$ 2,068	$ 6,923	$ 5,224	$ 10,149