Summary of Significant Accounting Policies Cash, Cash Equivalents and Marketable Securities (Tables)

12 Months Ended

Dec. 31, 2019

Cash, Cash Equivalents and Marketable Securities [Abstract]

Restrictions on Cash and Cash Equivalents [Table Text Block]

The following table provides a reconciliation of cash and cash equivalents and restricted cash reported within the consolidated balance sheet to same such amounts show in the consolidated statement of cash flows:

	As of December 31,
	2019		2018		2017		2016
Cash and cash equivalents	$	23,620	$	5,057	$	31,360	$	29,078
Restricted cash	2,015		2,047		1,967		1,851
	$	25,635	$	7,104	$	33,327	$	30,929