Amazon's earnings for the 2017 holiday season beat estimates as it continues to dominate the online retail market.

The bigger picture: The Wall Street Journal notes that the fourth quarter of 2017 was the first where the company — which has notoriously tight margins — drew a profit of more than $1 billion, which the company says included a "provisional" tax benefit of $789 million linked to the recently-passed tax reform bill.

The results come not long after Amazon jolted the healthcare market with news that it would create a new company with J.P. Morgan Chase and Berkshire Hathaway to "address health care" for their employees in the United States.

The gritty details:

• The company brought in $3.75 per-share in Q4 of 2017, vs. the $1.85 estimated by Wall Street, per CNBC.
• It's total quarterly profit was $1.9 billion. It was $749 million in the year-ago quarter.
• Net fourth-quarter sales rose rose to $60.5 billion, up from $43.7 in the year-ago quarter.

Note: This post has been clarified to show that Amazon dominates online retail, not physical retail as well.