Recent Accounting Pronouncements - Narrative (Details) - USD ($) $ in Thousands		9 Months Ended
	Jan. 01, 2018	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Retained earnings		$ 286,462		$ 271,023
Other comprehensive income, net of tax		$ 1,259	$ 600
Accounting Standards Update 2016-01
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Other comprehensive income, net of tax	$ 147