Stock Incentive Plan, Options and Warrants (Narrative) (Detail) - USD ($)				1 Months Ended	12 Months Ended
	Feb. 20, 2018	Jul. 25, 2017	Feb. 23, 2016	Feb. 28, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Dec. 04, 2005	Jan. 05, 2005
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Estimated forfeiture rate for calculating compensation cost								0.00%
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Stock Options					$ 0
2005 Stock Incentive Compensation Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized										366,667
2013 Stock Incentive Compensation Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized									2,500,000
Chief Executive Officer [Member] | Year 2017 One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated share-based compensation expense					$ 0
Employees and Consultant [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated share-based compensation expense							$ 400,000
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Accelerated shares, vesting							32,500
Accelerated shares, compensation expense							$ 200,000
Restricted stock awards, granted in period					235,296	111,112	80,903
Vested units					137,843	174,363	232,769
Restricted Stock | Members of BOD
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period					1 year
Allocated share-based compensation expense					$ 300,000
Restricted stock awards, granted in period					235,296
Fair value of restricted stock grant					$ 400,000
Restricted Stock | Board of Directors Chairman [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock awards, granted in period						70,548
Time-based Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total compensation expense					$ 500,000	$ 600,000	$ 1,600,000
Stock option expense, Recognition period					10 months 24 days
Unrecognized compensation expense, other than options					$ 200,000
Unrecognized compensation expense, period for recognition					10 months 24 days
Time-based Restricted Stock [Member] | Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated share-based compensation expense						1,500,000
Fair value of restricted stock grant					$ 843,486
Time-based Restricted Stock [Member] | Board Of Director Chairman And Non employee Member
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated share-based compensation expense					100,000	$ 100,000	300,000
Fair value of restricted stock grant							$ 500,000
Time-based Restricted Stock [Member] | Board Of Director Chairman And Non employee Member | Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period							1 year
Time-based Restricted Stock [Member] | Board Of Director Chairman And Non employee Member | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period							5 years
Time-based Restricted Stock [Member] | Members of BOD
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period						1 year
Allocated share-based compensation expense					$ 100,000	$ 300,000
Restricted stock awards, granted in period						111,112	70,548
Fair value of restricted stock grant						$ 400,000
Time-based Restricted Stock [Member] | Employees and Consultant [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period					5 years
Allocated share-based compensation expense					$ 1,400,000
Restricted stock awards, granted in period					1,835,257
Fair value of restricted stock grant					$ 3,200,000
Time-based Restricted Stock [Member] | Nonemployee [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock awards, granted in period							10,355
Warrants
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated share-based compensation expense					0	100,000	$ 200,000
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Accrued share-based compensation expense						$ 1,500,000
Accelerated shares, vesting						16,667
Accelerated shares, compensation expense					$ 100,000
Restricted stock awards, granted in period					2,678,743	688,836	260,000
Vested units					1,732,523	219,103	33,333
Restricted Stock Units (RSUs) [Member] | Chief Executive Officer [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period						3 years
Allocated share-based compensation expense					$ 100,000	$ 100,000
Restricted stock awards, granted in period						100,000
Fair value of restricted stock grant						$ 400,000
Restricted Stock Units (RSUs) [Member] | Former Chief Executive Officer [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period						2 years
Accelerated shares, vesting						66,667
Accelerated shares, compensation expense						$ 700,000
Restricted stock awards, granted in period						60,000
Fair value of restricted stock grant						$ 300,000
Restricted Stock Units (RSUs) [Member] | Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period							3 years
Allocated share-based compensation expense					500,000	700,000	$ 200,000
Total compensation expense					$ 2,400,000	$ 1,800,000	$ 600,000
Stock option expense, Recognition period					2 years 2 months 12 days
Restricted stock awards, granted in period						200,000	260,000
Fair value of restricted stock grant							$ 1,800,000
Unrecognized compensation expense, other than options					$ 1,900,000
Unrecognized compensation expense, period for recognition					2 years 2 months 12 days
Restricted Stock Units (RSUs) [Member] | Employees and Consultant Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period						3 years
Allocated share-based compensation expense					$ 400,000	$ 200,000
Fair value of restricted stock grant						$ 1,400,000
Restricted Stock Units (RSUs) [Member] | Consultant [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period						6 months
Restricted stock awards, granted in period						52,083
Fair value of restricted stock grant						$ 100,000
Restricted Stock Units (RSUs) [Member] | Consultant [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated share-based compensation expense					100,000
Restricted Stock Units (RSUs) [Member] | Consultant Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock awards, granted in period						276,753
Performance based restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated share-based compensation expense					$ 900,000	$ 3,500,000	$ 4,000,000
Accelerated shares, vesting							108,500
Accelerated shares, compensation expense							$ 500,000
Restricted stock awards, granted in period					785,000	716,600	2,134,100
Vested units					350,408	701,233	317,833
Performance based restricted stock | Chief Executive Officer [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Accelerated shares, compensation expense					$ 2,900,000
Restricted stock awards, granted in period			20,000		200,000
Performance based restricted stock | Chief Executive Officer [Member] | Year 2017 One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period						3 years
Restricted stock awards, granted in period						300,000
Fair value of restricted stock grant						$ 800,000
Performance based restricted stock | Chief Executive Officer [Member] | Year 2017 Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period						3 years
Restricted stock awards, granted in period						175,000
Fair value of restricted stock grant						$ 700,000
Performance based restricted stock | Chief Financial Officer [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock awards, granted in period			12,000	36,000
Performance based restricted stock | Chief Financial Officer [Member] | Year 2017 Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated share-based compensation expense					$ 100,000
Total compensation expense					200,000
Performance based restricted stock | Former Chief Executive Officer [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock awards, granted in period				60,000
Performance based restricted stock | Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period						3 years
Allocated share-based compensation expense					0
Total compensation expense					$ 200,000
Restricted stock awards, granted in period					135,000		30,000
Stock issued					83,250
Fair value of restricted stock grant					$ 300,000	$ 700,000
Performance based restricted stock | Employees [Member] | Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period					1 year
Performance based restricted stock | Employees [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period					2 years
Performance based restricted stock | Employees and Consultant [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period							3 years
Allocated share-based compensation expense					$ 0
Total compensation expense					500,000
Restricted stock awards, granted in period		41,600	69,994	164,978			2,104,100
Fair value of restricted stock grant							$ 15,400,000
Vested units	208,883
Performance based restricted stock | Employees and Consultant [Member] | February 28, 2107 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated share-based compensation expense					$ 600,000
Performance based restricted stock | Employees and Consultant [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated share-based compensation expense							$ 100,000
Performance based restricted stock | Consultant [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period					5 years
Restricted stock awards, granted in period					250,000
Fair value of restricted stock grant					$ 500,000
Performance based restricted stock | Employee 1 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period					3 years
Restricted stock awards, granted in period					200,000	200,000
Fair value of restricted stock grant					$ 400,000
Performance based restricted stock | Employee 2 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period					2 years
Restricted stock awards, granted in period					200,000
Fair value of restricted stock grant					$ 500,000
Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated share-based compensation expense					$ 0
Employee Stock Option [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated share-based compensation expense						$ 100,000