Income Taxes - Effective Income Tax Rate (Details)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Effective Income Tax Rate Reconciliation, Percent [Abstract]
Provision at statutory rate	12.50%	12.50%	12.50%
Foreign rate differential	3.10%	(7.10%)	(93.30%)
State income taxes, net of federal benefit	2.70%	3.00%	(1.40%)
Provision to return	0.80%	(1.00%)	9.30%
Tax credits	(2.70%)	(1.30%)	(0.60%)
Change in tax law	(1.10%)	(6.20%)	10.30%
Change in valuation allowance	(29.10%)	51.00%	17.00%
Change in unrecognized taxes	(4.70%)	13.80%	22.20%
Permanent differences	31.20%	(14.10%)	61.80%
Taxes on unremitted earnings	3.60%	3.90%	17.30%
Other	(1.70%)	0.40%	2.20%
Effective income tax rate	14.60%	54.90%	57.30%