Here's the packing list from the Olivia Alaska Facebook page…and no…you do not need to pack everything on it 
Packing requirements for a cruise to Alaska vary depending on activities, as well as your own personal needs. Try to pack clothing that is re-usable, can be wore more than once. If you're planning to buy t-shirts, hats, etc. on the ship or at ports, why not wear them on the cruise and pack less to begin with. And, it's always best to dress in layers for Alaska…be prepared for anything!
Travel Documents and Identification
Airline tickets or e-ticket confirmation
Cruise documents
Passports, Visas (if necessary)
Driver's license and auto insurance card - if you decide to rent a car
Medical insurance cards and medical history (especially if traveling alone)
Credit cards, ATM card (call credit card companies before traveling to alert them you are traveling outside your normal area)
Pre-paid phone card
Cash or traveler's checks
3 copies of airline tickets, cruise tickets, passports/visas, itinerary (pack 1 copy in carry on, 1 copy in checked luggage, and leave one copy with someone at home)
Contact numbers to report lost/stolen credit cards
Emergency numbers at home
Clothing
Bras
Underwear
Lingerie, Nightgown, Pajamas, Robe
Socks - exercise, walking, evening wear
Belts
Shoes (casual, dress, walking, hiking, exercise ,waterproof - break in new shoes before the trip)
Swim Suit, Thongs, Flip Flops (for onboard by the pool or spa)
Workout Clothes and Sports Bra
Dresses/outfits for formal/theme nights on ship
Shorts (Alaska can be 75 or more degrees some days)
Pants, Jeans, Khakis
Shirts, Blouses (casual & dress), T-Shirts
Waterproof windbreaker jacket
Sweatshirt or Sweater
Baseball caps, Hat, or Sun Visor
Raincoat with Hood
Rain pants
Gloves, Scarf, Knit Ski-cap (it gets cold on a glacier)
Clothing you can layer (long underwear, fleece, a waterproof/breathable shell)
Toiletries
Comb/Brush
Hair Gel, Mousse, Hair Spray
Toothbrush, toothpaste, floss, mouthwash
Deodorant
Make-up
Nail Polish
Tweezers
Nail Clippers and File
Razor and Shaving Cream
Blow Dryer (some find that one's on the ship are not strong enough)
Shampoo, conditioner, soap (cruise lines supply them, unless you have a favorite)
Sundries
Prescription drugs and essential medications (in carry on bag)
Motion Sickness Medicine (motion sickness tablets (Bonine, Dramamine, etc.), Scopolamine patch (requires a prescription), wrist bands (Sea Bands), Ginger (candy or capsules)
Ear plugs
Small first aid kit
Sun screen/sun block and lip sunblock
Hand lotion
Sewing kit
Empty folding tote bag - for souvenirs
Large insulated coffee mug
Photography & Electronic Equipment
Camera, Video Camera
Zoom and wide-angle Lenses
Tripod, Monopod
Extra film or memory cards
Extra batteries and/or battery chargers
Multi-plug extension cord or power strip
iPhone, iPod, iPad, MP3 Player
Laptop
Miscellaneous
Watch
Travel-size binoculars
Glasses, sunglasses, contacts, contact lens cleaner, reading glasses
Guidebooks and other port of call information
Reading material - books to read while on the plane or lounging by the pool
Business cards with email address to give out to new cruise friends
Email addresses of friends/relatives back home - for sending postcards or emails
Extra luggage name tags (in case yours are lost on the outbound trip)
Cash in small bills for tipping at the airport, hotel, and taxis
Small travel alarm clock (battery operated)
Zip loc bags of all sizes and garbage/laundry bags
Travel pillow for long airplane flights
Small backpack
Small flashlight
Small umbrella
Leaving Home Checklist
Have the post office hold your mail
Stop your newspaper or any deliveries, or have a friend or neighbor take them in for you
Make sure your pets are taken care of (at-home pet sitter or boarding kennel)
Have a friend or neighbor keep a look-out for your home while gone.
Put some lights on timers for the appearance that someone is home.
Leave copies of your passport, airline tickets, travelers checks and any credit cards you plan to use with a family member or trusted friend
Bring your travel and health insurance information and have it handy at all times
Distribute your ship communications cards to friends and relatives in case of emergency
Place a card with your name and address inside your luggage, as well as on the outside
Verify that your identification and travel tickets are in your carry-on bag and available at all times
Carry all documents, medicines, essentials, and valuables with you in your carry-on