Condensed Consolidated Statement of Changes in Stockholders' Equity (Unaudited) (Parenthetical) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Dec. 31, 2018	Mar. 31, 2018
Statement of Stockholders' Equity [Abstract]
Issuance of shares (in shares)	45,228	31,762	26,540
Value of shares issued	$ 131	$ 101	$ 82

For net-share settlement of share-based awards when the employer settles employees' income tax withholding obligations, this element represents the number of shares the employees use to repay the employer.

No definition available.

Name:	us-gaap_SharesPaidForTaxWithholdingForShareBasedCompensation
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration