Notes Payable - Schedule of Notes Payable (Parenthetical) (Detail)	Jun. 30, 2015	Dec. 31, 2014
Unsecured notes payable due to related parties; interest at 10% per annum; principal and accrued interest due at maturity in September 2015
Debt Instrument [Line Items]
Interest rate	10.00%	10.00%
Series A notes payable; interest at 8% per annum; principal and accrued interest due at maturity in October 2011 (past due)
Debt Instrument [Line Items]
Interest rate	8.00%	8.00%
Notes payable; interest at 8% per annum; principal and accrued interest due at December 1, 2014 (past due)
Debt Instrument [Line Items]
Interest rate	8.00%	8.00%
Notes payable, interest at 5% and 8% per annum; principal and interest due April 2015
Debt Instrument [Line Items]
Interest rate	5.00%	8.00%
Notes payable; interest at 5% per annum, principal and accrued interest due at June 10, 2015
Debt Instrument [Line Items]
Interest rate	5.00%
Notes payable; interest at 8% per annum, principal and accrued interest due at June 25, 2015
Debt Instrument [Line Items]
Interest rate	8.00%