Unaudited Quarterly Financial Data (Tables)
 12 Months Ended
Dec. 31, 2016
Quarterly Financial Information Disclosure [Abstract]  
Schedule of Quarterly Results
Quarterly results of operations for 2016 are summarized as follows:

 
First Quarter
 
Second Quarter
 
Third Quarter
 
Fourth Quarter
 
(In thousands except per share data)
 
 
 
 
 
 
 
 
2016:
 
 
 
 
 
 
 
Revenues
$
148,942

 
167,094

 
181,847

 
184,485

 
 
 
 
 
 
 
 
Earnings (loss)
$
17,259

 
26,286

 
33,736

 
23,612

 
 
 
 
 
 
 
 
Basic earnings (loss) per share:
 
 
 
 
 
 
 
Class A
$
4.88

 
7.43

 
9.54

 
6.68

Class B
$
2.44

 
3.72

 
4.77

 
3.34

 
 
 
 
 
 
 
 
Diluted earnings (loss) per share:
 
 
 
 
 
 
 
Class A
$
4.88

 
7.43

 
9.54

 
6.67

Class B
$
2.44

 
3.72

 
4.77

 
3.34


Quarterly results of operations for 2015 are summarized as follows:

 
First Quarter
 
Second Quarter
 
Third Quarter
 
Fourth Quarter
 
(In thousands except per share data)
 
 
 
 
 
 
 
 
2015:
 
 
 
 
 
 
 
Revenues
$
147,890

 
155,218

 
106,104

 
180,583

 
 
 
 
 
 
 
 
Earnings (loss)
$
21,326

 
28,858

 
16,221

 
31,991

 
 
 
 
 
 
 
 
Basic earnings (loss) per share:
 

 
 

 
 

 
 

Class A
$
6.03

 
8.16

 
4.59

 
9.05

Class B
$
3.02

 
4.08

 
2.29

 
4.52

 
 
 
 
 
 
 
 
Diluted earnings (loss) per share:
 

 
 

 
 

 
 

Class A
$
6.03

 
8.16

 
4.59

 
9.04

Class B
$
3.02

 
4.08

 
2.29

 
4.52