Lightning Cable in Washing Machine
I would caution you to consider that all Lightning cables have small chips (basically a little computer inside them) to control charging as well as signaling. It's not as damaging as putting a phone through the wash, but depending on the age of the cable and if it's physically intact - water could easily compromise the electronics in the connector. Especially when it's warped by the heat of the dryer or otherwise compromised physically.


  We have confirmed that the Lightning cable does have four chips embedded in it, plus some passive devices. Two of these chips are very simple (only a couple of transistors), and the third is an NXP NX20P3. However, the fourth and arguably most interesting of these is the TI chip.


Details of the chips are from http://www.chipworks.com/about-chipworks/overview/blog/inside-apple-lightning-cable

One trip on a new cable is probably low risk of damaging the phone if you use it, buy if the cable connector is cracked or that water damage causes corrosion, some time down the line that cable will fail. I'm sure it's designed to fail in a safe mode, but this isn't a situation where you have wires that can dry out harmlessly as you would expect if you had headphones that go through the wash or an older 30 pin cable design that was simply wire and plastic.