Summary of Significant Accounting Policies - Intangible Assets - Components of finite-lived intangible assets acquired (Details) - Apr. 30, 2015 - USD ($)	Total
Components of finite-lived intangible assets acquired
Total gross carrying amount	$ 1,559,000
Accumulated amortization	1,559,000
Net carrying amount	0
Customer Relationships
Components of finite-lived intangible assets acquired
Total gross carrying amount	758,000
Accumulated amortization	758,000
Net carrying amount	$ 0
Weighted Average Life	2 years
Trade Names
Components of finite-lived intangible assets acquired
Total gross carrying amount	$ 733,000
Accumulated amortization	733,000
Net carrying amount	$ 0
Weighted Average Life	5 years
Noncompete Agreement
Components of finite-lived intangible assets acquired
Total gross carrying amount	$ 68,000
Accumulated amortization	68,000
Net carrying amount	$ 0
Weighted Average Life	4 years