WASHINGTON – There was the weekend trip for President Obama and his daughters to New York, including a Broadway show and a private museum tour.

The ski trip to Aspen, Colo., for First Lady Michelle Obama in February.

And lots and lots of golf in Florida, Southern California and Martha's Vineyard, Mass.

Now, as the Obama family departs Friday on its annual holiday vacation to Hawaii, new estimates put the price tag of the Obamas' 2015 trips that were all or largely personal at $11.6 million for travel costs alone, based on government records, the conservative group Judicial Watch said.

That brings the overall cost of personal or largely personal travel to at least $70.5 million since Obama took office in 2009, the group said.

The costs of Air Force One and other government planes as well as helicopters and limos often raise questions about the need.

"My gosh, we can't afford it," said Tom Fitton of Judicial Watch, which is pushing for less personal travel.

But others call the costs a necessary part of security and convenience. "I don't think anyone on either side of the aisle is advocating for them to do less," said Dave Carney, a White House political director for President George H.W. Bush and a critic of what he called posh Obama vacations.

Necessary security

"No one wants to say we need less security and then something happens," he said.

The White House disputes the travel numbers, saying that some of the trips the group cites included work-related activities.

Obama's trip to California in June, for example, included a speech to U.S. Conference of Mayors in San Francisco as well as golf in Palm Springs. Michelle Obama's trip to the United Kingdom and Italy with her mother and daughters that same month included promotion of a girls' education initiative, participation in the delegation to the World's Fair, and a visit to U.S. military service members.

"The president recognizes that he is president of the United States 24 hours a day, seven days a week, wherever he happens to be," said White House spokesman Eric Schultz. "We believe the American people would not begrudge their president for taking some downtime."

Obama does not take an extraordinary amount of vacation time.

He's taken 23 vacations spanning all or part of 177 days, according to Mark Knoller, a CBS News White House correspondent who maintains an authoritative record of presidential activities.

By comparison, President George W. Bush at this point in his tenure had made 68 visits to his Texas ranch spanning all or part of 441 days, and 10 visits to his family's home in Kennebunkport, Maine, spanning all or part of 39 days, according to Knoller.

Criticism of presidential vacations goes back to John Adams, who frequently traveled from the capital to his Massachusetts home, said Brendan J. Doherty, a political-science professor at the U.S. Naval Academy.

Never off duty

In the modern era, traveling staff and ever-present telecommunications allow presidents to work even from vacation if they choose.

"Presidents are always on the job," Doherty said. "They are never truly off the clock."

The 2015 cost estimates from Judicial Watch primarily include the price for travel for 11 trips to New York City, Aspen, Chicago, Los Angeles, Palm Springs, Martha's Vineyard and Palm City, Fla. It includes last year's annual trip to Hawaii.

Some trips include the entire family, while others are taken by individual members. Many of the trips of the first lady and daughters, though, are unknown.

In response to series of recent Judicial Watch public records requests, the Air Force revealed that it costs $206,337 per hour to fly and operate the president's plane, Air Force One. The cost has grown considerably in recent years. In 2012, the Air Force estimated it cost $179,750 per hour, according to the Congressional Research Service.

Other costs are not generally made public, including the cost of housing Secret Service and White House staff, transporting limousines, helicopters and other equipment, rental cars, office space, food, even security upgrades such as adding bullet-resistant glass and more phone lines.

The first family picks up the tab for housing when they are on vacation. Published reports indicate that the Obamas spend $25,000 per week for their vacation home in Hawaii and $50,000 a week for their private vacation home, the Blue Heron Farm, on Martha's Vineyard.