Tucked into the Republican legislation to fund Immigration and Customs Enforcement (ICE) and Customs and Border Protection (CBP), a $1 billion paragraph is drawing attention and driving headlines.

(Here is the link, go to page 5.)

The proposal is for "$1,000,000,000 for the purposes of security adjustments and upgrades, including within the perimeter fence of the White House Compound to support enhancements by the United States Secret Service relating to the East Wing Modernization Project."

That is a staggering lack of detail.

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The $1 billion request is tied directly to the transformation of the East Wing into a massive ballroom, though limited to "security"-related needs.

But these details leave open the idea that some security improvements, including below-ground work, could affect the building of the ballroom itself, and managing of those costs.

Today, the director of the Secret Service held a closed door briefing with Senate Republicans and responded to questions from lawmakers about the proposal.

What did he tell them the money was for? I was able to obtain a copy of the list he gave senators.

• $220 million: "White House Complex Hardening." That is listed as above and below-ground security, including bulletproof glass, drone detection and "a host of other national security functions."
• $180 million: "Visitors Screening Facility." The description defines such a facility ("secure and efficient screening") but does not provide more detail.
• $175 million: "Training." This will be for the U.S. Secret Service and its facilities. No other details provided.
• $175 million: "Enhancements for Protectee Security." Few details are given here, except that this could include "frequently visited venues."
• $150 million: "Evolving threats and technology." This is said to be for special operations to counter drones, airspace intrusions, biological threats and other technological needs.
• $100 million: "Events of National Significance." No specific events are mentioned here, just that this is about "large-scale" and high profile national events.

What do senators think? Republicans I spoke with seemed convinced that the White House needs more security. And some, like Sen. Josh Hawley of Missouri, told me they are more or less on board with this request.

But a significant group wants far more detail. That includes Senate Appropriations Chair Susan Collins, R-Maine, who told me, "I've asked for a lot more data."

What's next?This package is poised for a full Senate vote as soon as next week.