Number of new stock issued during the period.

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-Publisher FASB
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Name:	us-gaap_StockIssuedDuringPeriodSharesNewIssues
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

Stockholders' Equity - Common Stock (Details) - USD ($) $ in Thousands	3 Months Ended			9 Months Ended
	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Sep. 30, 2019	Sep. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Proceeds from stock option exercises				$ 1,705	$ 0
Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock newly-issued during the period (in shares)	922,784	79,616	48,634	229,261