Segment Information (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Segment Reporting Information [Line Items]
Revenue	[1]	$ 278,589	$ 207,636	$ 786,671	$ 615,210
Gross profit		209,202	157,576	595,045	467,300
Clear Aligner
Segment Reporting Information [Line Items]
Revenue		243,668	198,292	706,802	586,138
Gross profit		189,270	156,205	552,663	461,502
Scanner
Segment Reporting Information [Line Items]
Revenue		34,921	9,344	79,869	29,072
Gross profit		$ 19,932	$ 1,371	$ 42,382	$ 5,798

[1] {F|ahBzfndlYmZpbGluZ3MtaHJkcmoLEgZYTUxEb2MiXlhCUkxEb2NHZW5JbmZvOmE4MmYxNjA2YzdiMDQ5ZjQ4NWQ0OTY5NTEzMGQ5ZmQ1fFRleHRTZWxlY3Rpb246QkQyQjNFOThCNEVFMUZBRUExM0M3MDg5MjYwRjAzQzAM}