Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Income Tax Disclosure [Line Items]
Effective combined Federal and state tax rate	20.90%	10.20%	9.90%	8.50%
Statutory federal tax rate (as a percent)			21.00%
Income Tax Expense (Benefit)	$ 10,793	$ 4,697	$ 9,820	$ 6,349
Increase (decrease) in valuation allowance	4,000		(4,200)
Deferred Tax Asset Investment In Subsidiary [Member]
Income Tax Disclosure [Line Items]
Income Tax Expense (Benefit)			(4,200)
Increase (decrease) in valuation allowance	4,000		(4,200)
Valuation allowance	$ 23,400		$ 23,400