Property and Equipment - Components of Property and Equipment (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 50,940	$ 24,156
Less accumulated depreciation and amortization	(12,780)	(8,725)
Property and equipment, net	38,160	15,431
Capitalized Internal-Use Software
Property Plant And Equipment [Line Items]
Property and equipment, gross	13,119	11,104
Furniture and Fixtures
Property Plant And Equipment [Line Items]
Property and equipment, gross	4,156	1,383
Hosting Equipment
Property Plant And Equipment [Line Items]
Property and equipment, gross	11,630	7,931
Computer Equipment and Software
Property Plant And Equipment [Line Items]
Property and equipment, gross	3,583	1,680
Leasehold Improvements
Property Plant And Equipment [Line Items]
Property and equipment, gross	12,438	1,717
Construction in Progress
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 6,014	$ 341