v2.4.0.6
Consolidating financial information (Details 4) (USD $)
In Thousands, unless otherwise specified
 12 Months Ended
Dec. 31, 2012
Dec. 31, 2011
Dec. 31, 2010
Cash flows from operating activities:      
Net cash (used in) provided by operating activities $ 167,078 $ 55,935  
Cash flows (used in) provided by investing activities:      
Acquisitions and investments, net of cash acquired (80,496) (591,583) (78,180)
Proceeds from sale of equity investments 27,925 8,500 2,000
Construction in progress (456,205) (113,072) (44,146)
Short-term loan to Idaho Wind   22,781  
Change in restricted cash (11,589) (5,668) 945
Biomass development costs (480) (931) (2,286)
Proceeds from sale of assets   8,500  
Purchase of property, plant and equipment (2,902) (2,035)  
Net cash (used in) provided by investing activities (523,747) (682,008)  
Cash flows (used in) provided by financing activities:      
Proceeds from issuance of convertible debentures 230,640   74,575
Proceeds from issuance of long-term debt   460,000  
Repayment of long-term debt (284,783) (21,589) (18,882)
Proceeds from project-level debt 291,865 100,794  
Net proceeds from issuance of equity 66,294 155,424 72,767
Deferred financing costs (31,217) (26,373) (7,941)
Payments for revolving credit facility (60,800)   (20,000)
Proceeds from revolving credit facility borrowings 69,800 58,000 20,000
Equity investment from noncontrolling interest 225,000   200
Dividends paid (144,117) (85,029) (65,028)
Net cash provided by (used in)financing activities 362,682 641,227  
Net (decrease) increase in cash and cash equivalents 6,013 15,154  
Less cash at discontinued operations (6,473)    
Cash and cash equivalents at beginning of period 60,651 45,497 49,850
Cash and cash equivalents at end of period 60,191 60,651 45,497
Guarantor Subsidiaries
      
Cash flows from operating activities:      
Net cash (used in) provided by operating activities (9,924) 20,963  
Cash flows (used in) provided by investing activities:      
Acquisitions and investments, net of cash acquired (206,535) 12,143  
Proceeds from sale of equity investments 27,925    
Construction in progress (456,205) (113,072)  
Short-term loan to Idaho Wind   21,465  
Change in restricted cash (11,589) (5,668)  
Biomass development costs (480) (931)  
Proceeds from sale of assets   8,500  
Purchase of property, plant and equipment (1,794) (1,975)  
Net cash (used in) provided by investing activities (235,608) (79,538)  
Cash flows (used in) provided by financing activities:      
Repayment of long-term debt (284,783) (21,589)  
Proceeds from project-level debt 291,865 100,794  
Net proceeds from issuance of equity (1,398)    
Deferred financing costs (19,744)    
Payments for revolving credit facility (30,800)    
Proceeds from revolving credit facility borrowings 69,800 8,000  
Equity investment from noncontrolling interest 225,000    
Dividends paid (13,084) (3,247)  
Net cash provided by (used in)financing activities 236,856 83,958  
Net (decrease) increase in cash and cash equivalents (8,676) 25,383  
Less cash at discontinued operations (6,473)    
Cash and cash equivalents at beginning of period 58,370 32,987  
Cash and cash equivalents at end of period 43,221 58,370  
Curtis Palmer
      
Cash flows from operating activities:      
Net cash (used in) provided by operating activities 1,123 45  
Cash flows (used in) provided by investing activities:      
Purchase of property, plant and equipment (1,108) (60)  
Net cash (used in) provided by investing activities (1,108) (60)  
Cash flows (used in) provided by financing activities:      
Net (decrease) increase in cash and cash equivalents 15 (15)  
Cash and cash equivalents at beginning of period (15)    
Cash and cash equivalents at end of period   (15)  
APC
      
Cash flows from operating activities:      
Net cash (used in) provided by operating activities 175,879 34,927  
Cash flows (used in) provided by investing activities:      
Acquisitions and investments, net of cash acquired (287,031) (603,726)  
Short-term loan to Idaho Wind   1,316  
Net cash (used in) provided by investing activities (287,031) (602,410)  
Cash flows (used in) provided by financing activities:      
Proceeds from issuance of long-term debt 230,640 460,000  
Net proceeds from issuance of equity 67,692 155,424  
Deferred financing costs (11,473) (26,373)  
Proceeds from revolving credit facility borrowings 30,000 50,000  
Dividends paid (131,033) (81,782)  
Net cash provided by (used in)financing activities 125,826 557,269  
Net (decrease) increase in cash and cash equivalents 14,674 (10,214)  
Cash and cash equivalents at beginning of period 2,296 12,510  
Cash and cash equivalents at end of period $ 16,970 $ 2,296