Accumulated Other Comprehensive Loss (Tables)
 9 Months Ended
Sep. 30, 2016
Equity [Abstract]  
Summary of Accumulated Other Comprehensive Loss
The following tables summarize the changes in the accumulated other comprehensive loss balance, net of tax, by component as follows (in thousands):
 
Foreign Currency
 
Effective Portion of Change in Fair Value of Derivatives
 
Proportionate Share of Equity Investee’s OCI
 
Total
Balances at December 31, 2014
$
(19,338
)
 
$
(26,672
)
 
$
(7,903
)
 
$
(53,913
)
Other comprehensive loss before reclassifications
(21,900
)
 
(16,257
)
 
(6,895
)
 
(45,052
)
Amounts reclassified from accumulated other comprehensive loss due to termination of interest rate derivatives
—

 
11,221

 
—

 
11,221

Amounts reclassified from accumulated other comprehensive loss
—

 
9,546

 
1,582

 
11,128

Net current period other comprehensive loss
(21,900
)
 
4,510

 
(5,313
)
 
(22,703
)
Balances at September 30, 2015
$
(41,238
)
 
$
(22,162
)
 
$
(13,216
)
 
$
(76,616
)
Less: accumulated other comprehensive loss attributable to noncontrolling interest, September 30, 2015
—

 
(950
)
 
—

 
(950
)
Accumulated other comprehensive loss attributable to Pattern Energy, September 30, 2015
$
(41,238
)
 
$
(21,212
)
 
$
(13,216
)
 
$
(75,666
)
 
Foreign Currency
 
Effective Portion of Change in Fair Value of Derivatives
 
Proportionate Share of Equity Investee’s OCI
 
Total
Balances at December 31, 2015
$
(48,285
)
 
$
(13,462
)
 
$
(12,131
)
 
$
(73,878
)
Other comprehensive income (loss) before reclassifications
9,874

 
(30,990
)
 
(11,684
)
 
(32,800
)
Amounts reclassified from accumulated other comprehensive loss
—

 
8,359

 
2,752

 
11,111

Net current period other comprehensive income (loss)
9,874

 
(22,631
)
 
(8,932
)
 
(21,689
)
Balances at September 30, 2016
$
(38,411
)
 
$
(36,093
)
 
$
(21,063
)
 
$
(95,567
)
Less: accumulated other comprehensive loss attributable to noncontrolling interest, September 30, 2016
—

 
(1,418
)
 
—

 
(1,418
)
Accumulated other comprehensive loss attributable to Pattern Energy, September 30, 2016
$
(38,411
)
 
$
(34,675
)
 
$
(21,063
)
 
$
(94,149
)