Summary of Significant Accounting Policies - Narrative (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2019 USD ($) subsidiary	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Number of subsidiaries | subsidiary	2
One-time, non cash charge to income tax expense	$ 0	$ 0	$ 1,365
Increase to accumulated other comprehensive income, net of tax			9,053
Decrease to retained earnings			(9,053)
Compensation expense	$ 2,300	$ 2,500	2,700
Retained Earnings
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Increase to accumulated other comprehensive income, net of tax			(9,100)
Decrease to retained earnings			9,100
AOCI Attributable to Parent
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Increase to accumulated other comprehensive income, net of tax			9,100
Decrease to retained earnings			$ (9,100)