Condensed Consolidated Statement of Changes in Stockholders' Equity (Parenthetical) - shares	3 Months Ended
Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2018	Mar. 31, 2018
Statement of Stockholders' Equity [Abstract]
Common stock withheld to satisfy income tax withholding obligations relating to restricted stock units (in shares)	26,801	164,580	24,255	222,202

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